Lag & Lead - Revision history

S173891 at 14:52, 28 February 2021

2021-02-28T14:52:05Z

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	== Importance of Lag and Lead ==		== Importance of Lag and Lead ==
	As a project is only a temporary endeavor<ref name="PMBOK">Project Management Institute, Inc., ''Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE'', (Project Management Institute, Inc. (PMI). 6th Edition), Part 1 chapter 6</ref> therefore there is a start and a finish date. In most cases the finish date is decided in the process of planning a project. When the project starts it is the project managers job to keep the project on schedule and avoid any major delays. A project that is done well but not done on time can be viewed as a project management failure, as the project did not fail but the management made mistakes as the project was not done on time. The Prince2 standard states ''"Plans provide the backbone of the management information required for any project; without a plan there can be no control."''<ref name="Prince2">Nigel Bennett, Robert Buttrick, Phil Stanton, Project Management: "Managing Successful Projects with PRINCE2'', (AXELOS Limited). 6th Edition 2017, Chapter 9), ~~Part 1 chapter 6~~</ref> This states the importance of a plan that includes a timeframe on what will delivered by who and how. Before the start of a project or in the beginning of the project, the management team will make a schedule for the project. There are different parts that goes into the making of a schedule. The parts include:		As a project is only a temporary endeavor<ref name="PMBOK">Project Management Institute, Inc., "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE", (Project Management Institute, Inc. (PMI). 6th Edition), Part 1 chapter 6, https://app-knovel-com.proxy.findit.dtu.dk/web/toc.v/cid:kpGPMBKP02/viewerType:toc//root_slug:viewerType%3Atoc/url_slug:root_slug%3Aguide-project-management?kpromoter=federation</ref> therefore there is a start and a finish date. In most cases the finish date is decided in the process of planning a project. When the project starts it is the project managers job to keep the project on schedule and avoid any major delays. A project that is done well but not done on time can be viewed as a project management failure, as the project did not fail but the management made mistakes as the project was not done on time. The Prince2 standard states ''"Plans provide the backbone of the management information required for any project; without a plan there can be no control."''<ref name="Prince2">Nigel Bennett, Robert Buttrick, Phil Stanton, Project Management: "Managing Successful Projects with PRINCE2", (AXELOS Limited). 6th Edition 2017, Chapter 9, https://www.axelos.com/store/book/managing-successful-projects-with-prince2-2017</ref> This states the importance of a plan that includes a timeframe on what will delivered by who and how. Before the start of a project or in the beginning of the project, the management team will make a schedule for the project. There are different parts that goes into the making of a schedule. The parts include:
	# Planning the Management Schedule<ref name="PMBOK" />		# Planning the Management Schedule<ref name="PMBOK" />
	# Defining the activities<ref name="PMBOK" />		# Defining the activities<ref name="PMBOK" />
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	[[File:Lag.png\|thumb\|300px\|Figure 2. An illustration of Lag between two activities. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]		[[File:Lag.png\|thumb\|300px\|Figure 2. An illustration of Lag between two activities. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]
	In Project Management: A guide to the Project Management Body of Knowledge lead is defined as ''“A lead is the amount of time a successor activity can be advanced with respect to a predecessor activity.”''<ref name="PMBOK" />. The ISO standard ISO 21500 defines lead as ''“Attribute applied to a logical relationship to advance the start or end of an activity”''<ref name="ISO">Dansk Standard, DS/ISO ~~2500~~, Dansk standard 2nd edition)</ref>.. These two definitions are two ways of saying a lead set the amount of time an activity can start before the previous are finished. When using lead the two activities will be done in parallel during the lead time. Figure 1 shows an illustration of lead time.		In Project Management: A guide to the Project Management Body of Knowledge lead is defined as ''“A lead is the amount of time a successor activity can be advanced with respect to a predecessor activity.”''<ref name="PMBOK" />. The ISO standard ISO 21500 defines lead as ''“Attribute applied to a logical relationship to advance the start or end of an activity”''<ref name="ISO">Dansk Standard, "DS/ISO 21500", Dansk standard 2nd edition, https://webshop.ds.dk/da-dk/standard/03-100-40-forskning-og-udvikling/ds-iso-215002013</ref>.. These two definitions are two ways of saying a lead set the amount of time an activity can start before the previous are finished. When using lead the two activities will be done in parallel during the lead time. Figure 1 shows an illustration of lead time.

S173891 at 14:44, 28 February 2021

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	== Importance of Lag and Lead ==		== Importance of Lag and Lead ==
	As a project is only temporary endeavor<ref name="PMBOK">Project Management Institute, Inc., ''Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE'', (Project Management Institute, Inc. (PMI). 6th Edition), Part 1 chapter 6</ref> therefore there is a start and a finish date. In most cases the finish date is decided in the process of planning a project. When the project starts it is the project managers job to keep the project on schedule and avoid any major delays. A project that is done well but not done on time can be viewed as a project management failure, as the project did not fail but the management made mistakes as the project was not done on time. The Prince2 ~~standart~~ states ''"Plans provide the backbone of the management information required for any project; without a plan there can be no control."''<ref name="Prince2">Nigel Bennett, Robert Buttrick, Phil Stanton, Project Management: "Managing Successful Projects with PRINCE2'', (AXELOS Limited). 6th Edition 2017, Chapter 9), Part 1 chapter 6</ref> This states the importance of a plan that includes timeframe, what will ~~deliver~~ by who and how. Before the start of a project or in the beginning of the project management team will make a schedule for the project. There are different parts that goes into the making of a schedule. The parts include:		As a project is only a temporary endeavor<ref name="PMBOK">Project Management Institute, Inc., ''Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE'', (Project Management Institute, Inc. (PMI). 6th Edition), Part 1 chapter 6</ref> therefore there is a start and a finish date. In most cases the finish date is decided in the process of planning a project. When the project starts it is the project managers job to keep the project on schedule and avoid any major delays. A project that is done well but not done on time can be viewed as a project management failure, as the project did not fail but the management made mistakes as the project was not done on time. The Prince2 standard states ''"Plans provide the backbone of the management information required for any project; without a plan there can be no control."''<ref name="Prince2">Nigel Bennett, Robert Buttrick, Phil Stanton, Project Management: "Managing Successful Projects with PRINCE2'', (AXELOS Limited). 6th Edition 2017, Chapter 9), Part 1 chapter 6</ref> This states the importance of a plan that includes a timeframe on what will delivered by who and how. Before the start of a project or in the beginning of the project, the management team will make a schedule for the project. There are different parts that goes into the making of a schedule. The parts include:
	# Planning the Management Schedule<ref name="PMBOK" />		# Planning the Management Schedule<ref name="PMBOK" />
	# Defining the activities<ref name="PMBOK" />		# Defining the activities<ref name="PMBOK" />
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	== Downside to Lag and Lead ==		== Downside to Lag and Lead ==
	Lag and Lead is not a tool but a technique, ~~therefor~~ there are very ~~little are limitation~~. Lag and Lead are more useful if ~~use~~ together with another tool, this could be the network diagram or the critical path methods as suggested in the article. There are also other scheduling methods where Lag and Lead are used. Another limitation can be that Lag and Lead can be hard to identify at the beginning of the project and therefore they have to be adjusted during the project. It can also be hard for the project manager alone to identify all the Lag and Lead, that means that if the project manager alone is ~~reasonable~~ for the Lag and Lead the estimate will be more off than if the estimates are made with the project management team and with input from the project team. Activities can have Lag and Lead with different types of relationships, however as stated the Finish-to-start is the most used one. A Start-to-finish relationship can in most cases be change to a finish-to-start as the defining activity is swapped. This is not a limitation, but this has caused confusion and lead some sources online to say that two activities with a lead can only have a Finish-to-start relationship. However, it depends on which activities are depending on what other activities. On figure 7 two examples of the dependency can be seen. If activity B is more depend on activity E than the other way around the relationship will be Finish-to-start if the activities are sequences as shown on figure 7(Example 1). If activity E is more depended on activity B the relationship will be Start-to-Finish if the sequences are as shown on figure 7(Example 2). There a project management team should keep an overview of which activities are depending on what.		Lag and Lead is not a tool but a technique, therefore there are very few limitations. Lag and Lead are more useful if used together with another tool, this could be the network diagram or the critical path methods as suggested in the article. There are also other scheduling methods where Lag and Lead are used. Another limitation can be that Lag and Lead can be hard to identify at the beginning of the project and therefore they have to be adjusted during the project. It can also be hard for the project manager alone to identify all the Lag and Lead, that means that if the project manager alone is responsible for the Lag and Lead the estimate will be more off than if the estimates are made with the project management team and with input from the project team. Activities can have Lag and Lead with different types of relationships, however as stated the Finish-to-start is the most used one. A Start-to-finish relationship can in most cases be change to a finish-to-start as the defining activity is swapped. This is not a limitation, but this has caused confusion and lead some sources online to say that two activities with a lead can only have a Finish-to-start relationship. However, it depends on which activities are depending on what other activities. On figure 7 two examples of the dependency can be seen. If activity B is more depend on activity E than the other way around the relationship will be Finish-to-start if the activities are sequences as shown on figure 7(Example 1). If activity E is more depended on activity B the relationship will be Start-to-Finish if the sequences are as shown on figure 7(Example 2). There a project management team should keep an overview of which activities are depending on what.
	[[File:Lead_relationship.png\|thumb\|center\|400px\|Figure 7. Examples of two types of Lead relationships in a sequence.]]		[[File:Lead_relationship.png\|thumb\|center\|400px\|Figure 7. Examples of two types of Lead relationships in a sequence.]]


			== Annotated bibliography ==
			*'''Project Management Institute, Inc., "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE", (Project Management Institute, Inc. (PMI). 6th Edition) - Page 192-193'''
			The book explains the concept of Lag and Lead as a part of the sequencing activities process. The book, which is a part of the PMI standard gives a definition of Lag and Lead according to this standard. The explaination is based on their definition of Lag and Lead. The book explains most concepts in project management and therefore the is also an explanation if a network diagram and the critical path.

			*'''iZenBrigde, "What is Lead and Lag", https://www.izenbridge.com/blog/what-is-lead-lag'''
			This explanation is based on the PMI standard, however this is made clearer with figures and examples. iZenBrigde also explains the relationship between tasks related to Lag and Lead. There is also a video with an explanation of Lag and Lead in the articles, that provides a basic explanation to the concept. The most common sources of confusion are pointed out and explained. At the end of the article there is a Q&A with an explanation of why Lag and Lead are important in project management.

			* '''Project-Management.info, "What Are Leads and Lags in Project Management?", https://project-management.info/leads-and-lags//'''
			An article on Lag and Lead in project management that is based on PMI standard, with an example on how to calculate the total during with the Lag and Lead between activities. The article talks about examples in IT-project and about how being aware of Lag and Lead can help project managers safe time during the execution.

			*'''iZenBrigde on YouTube, "PMBOK 6: Critical Path Method", https://www.youtube.com/watch?v=eZgv1BW1lCU'''
			Video explanation on Critical path method by iZenBrigde. The video explains how to use the critical path method in practice and how it can be helpful. The video explains how to calculate the early start, earlier finish, late start, late finish, and the float which is needed to find the critical path.



	== References ==		== References ==
	<references />		<references />

S173891: /* Limitations */

2021-02-28T12:46:35Z

Limitations

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	== ~~Limitations~~ ==		== Downside to Lag and Lead ==
	Lag and Lead is not a tool but a technique, there are limitation. Lag and Lead are more useful if use together with another tool, this could be the network diagram or the critical path methods as suggested in the article. There are also other scheduling methods where Lag and Lead are used. Another limitation can be that Lag and Lead can be hard to identify at the beginning of the project and therefore they have to be adjusted during the project. It can also be hard for the project manager alone to identify all the Lag and Lead, that means that if the project manager alone is reasonable for the Lag and Lead the estimate will be more off than if the estimates are made with the project management team and with input from the project team. Activities can have Lag and Lead with different types of relationships, however as stated the Finish-to-start is the most used one. A Start-to-finish relationship can in most cases be change to a finish-to-start as the defining activity is swapped. This is not a limitation, but this has caused confusion and lead some sources online to say that two activities with a lead can only have a Finish-to-start relationship. However, it depends on which activities are depending on what other activities. On figure 7 two examples of the dependency can be seen. If activity B is more depend on activity E than the other way around the relationship will be Finish-to-start if the activities are sequences as shown on figure 7(Example 1). If activity E is more depended on activity B the relationship will be Start-to-Finish if the sequences are as shown on figure 7(Example 2). There a project management team should keep an overview of which activities are depending on what.		Lag and Lead is not a tool but a technique, therefor there are very little are limitation. Lag and Lead are more useful if use together with another tool, this could be the network diagram or the critical path methods as suggested in the article. There are also other scheduling methods where Lag and Lead are used. Another limitation can be that Lag and Lead can be hard to identify at the beginning of the project and therefore they have to be adjusted during the project. It can also be hard for the project manager alone to identify all the Lag and Lead, that means that if the project manager alone is reasonable for the Lag and Lead the estimate will be more off than if the estimates are made with the project management team and with input from the project team. Activities can have Lag and Lead with different types of relationships, however as stated the Finish-to-start is the most used one. A Start-to-finish relationship can in most cases be change to a finish-to-start as the defining activity is swapped. This is not a limitation, but this has caused confusion and lead some sources online to say that two activities with a lead can only have a Finish-to-start relationship. However, it depends on which activities are depending on what other activities. On figure 7 two examples of the dependency can be seen. If activity B is more depend on activity E than the other way around the relationship will be Finish-to-start if the activities are sequences as shown on figure 7(Example 1). If activity E is more depended on activity B the relationship will be Start-to-Finish if the sequences are as shown on figure 7(Example 2). There a project management team should keep an overview of which activities are depending on what.
	[[File:Lead_relationship.png\|thumb\|center\|400px\|Figure 7. Examples of two types of Lead relationships in a sequence.]]		[[File:Lead_relationship.png\|thumb\|center\|400px\|Figure 7. Examples of two types of Lead relationships in a sequence.]]

	== References ==		== References ==
	<references />		<references />

S173891 at 12:25, 28 February 2021

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	There are also two definitions of Lag one from Project Management: A guide to the Project Management Body of Knowledge and one from the ISO 21500. The Project Management: A guide to the Project Management Body of Knowledge definition of lag is ''“A lag is the amount of time a successor activity will be delayed with respect to a predecessor activity.”''<ref name="PMBOK" /> . The definition in the ISO 21500 of lag is ''“Attribute applied to a logical relationship to delay the start or end of an activity”''<ref name="ISO"/>. Again, this is two ways of defining the same thing, that Lag means an activity takes place a set amount of time after the previous. Lag should one be applied if there is logical reason for it. Figure 2 shows an illustration of lag time.		There are also two definitions of Lag one from Project Management: A guide to the Project Management Body of Knowledge and one from the ISO 21500. The Project Management: A guide to the Project Management Body of Knowledge definition of lag is ''“A lag is the amount of time a successor activity will be delayed with respect to a predecessor activity.”''<ref name="PMBOK" /> . The definition in the ISO 21500 of lag is ''“Attribute applied to a logical relationship to delay the start or end of an activity”''<ref name="ISO"/>. Again, this is two ways of defining the same thing, that Lag means an activity takes place a set amount of time after the previous. Lag should one be applied if there is logical reason for it. Figure 2 shows an illustration of lag time. Lag should not be included in the duration of the activity as no-one needs to work on the activity during the Lag<ref name="project-info">Project-Management.info, "What Are Leads and Lags in Project Management?", https://project-management.info/leads-and-lags// </ref>.

S173891 at 12:10, 28 February 2021

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	=== Project Schedule Network Diagram ===		=== Project Schedule Network Diagram ===
	Lag and Lead is a part of the creation of the Project Schedule Network Diagram. The network diagram shows the logical relationship between activities. It is produced manually or with a project management software. As the network diagram is a graphical representation of the schedule the Lag and Lead are also added to have the information on when Lag and Lead is used shown graphical.		Lag and Lead is a part of the creation of the Project Schedule Network Diagram also called [[Project Network Diagram]]. The network diagram shows the logical relationship between activities. It is produced manually or with a project management software. As the network diagram is a graphical representation of the schedule the Lag and Lead are also added to have the information on when Lag and Lead is used shown graphical.

S173891 at 12:09, 28 February 2021

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	=== Critical Path Method ===		=== Critical Path Method ===
	[[File:Critical_path_box.png\|thumb\|300px\|Figure 6. Activity box for the Critical Path Method. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]		[[File:Critical_path_box.png\|thumb\|300px\|Figure 6. Activity box for the Critical Path Method. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]
	After having done the network diagram ~~the~~ [[The Critical Path Method (CPM)]] can be used to identify the Critical path in a project. When identifying the critical path, the Lag and Lead are used. In the critical path the earliest start and finish day are calculated as well as the latest start and finish day and the float. The float is not to be confused with the Lag and Lead. Float is also known as slack, and it means the time an activity can be push without interfering with the project finish. In the critical path methods, the box shown in figure 6 is filled out for all activities.		After having done the network diagram [[The Critical Path Method (CPM)]] can be used to identify the Critical path in a project. When identifying the critical path, the Lag and Lead are used. In the critical path the earliest start and finish day are calculated as well as the latest start and finish day and the float. The float is not to be confused with the Lag and Lead. Float is also known as slack, and it means the time an activity can be push without interfering with the project finish. In the critical path methods, the box shown in figure 6 is filled out for all activities.
	In order to calculate the critical path, you make a network diagram but with a box like the one shown in figure 4 for each activity. Then on a forward path the early start and finish date is calculated. The first activity starts on day one.		In order to calculate the critical path, you make a network diagram but with a box like the one shown in figure 4 for each activity. Then on a forward path the early start and finish date is calculated. The first activity starts on day one.
	*Early finish day is calculated by: Early start day + duration – 1		*Early finish day is calculated by: Early start day + duration – 1

S173891 at 12:08, 28 February 2021

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	When using Lag and Lead the project management team determines the dependencies between activities that may require a Lead or a Lag. Using Lag and Lead should not replace schedule logic and the duration estimates made by the teams should not include any Lags and Leads. The team should document the activities and the related assumptions <ref name="PMBOK" />.		When using Lag and Lead the project management team determines the dependencies between activities that may require a Lead or a Lag. Using Lag and Lead should not replace schedule logic and the duration estimates made by the teams should not include any Lags and Leads. The team should document the activities and the related assumptions <ref name="PMBOK" />. Figure 5 shows a Project Schedule Network Diagram.
	[[File:Network_diagram.png\|thumb\|center\|600px\|Figure 5. A Project Schedule Network Diagram with Lad and Lead. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]		[[File:Network_diagram.png\|thumb\|center\|600px\|Figure 5. A Project Schedule Network Diagram with Lad and Lead. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]

	=== Critical Path Method ===		=== Critical Path Method ===
	[[File:Critical_path_box.png\|thumb\|300px\|Figure 6. Activity box for the Critical Path Method. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]		[[File:Critical_path_box.png\|thumb\|300px\|Figure 6. Activity box for the Critical Path Method. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]
	After having done the network diagram the Critical ~~path method~~ can be used to identify the Critical path in a project. When identifying the critical path, the Lag and Lead are used. In the critical path the earliest start and finish day are calculated as well as the latest start and finish day and the float. The float is not to be confused with the Lag and Lead. Float is also known as slack, and it means the time an activity can be push without interfering with the project finish. In the critical path methods, the box shown in figure 6 is filled out for all activities.		After having done the network diagram the [[The Critical Path Method (CPM)]] can be used to identify the Critical path in a project. When identifying the critical path, the Lag and Lead are used. In the critical path the earliest start and finish day are calculated as well as the latest start and finish day and the float. The float is not to be confused with the Lag and Lead. Float is also known as slack, and it means the time an activity can be push without interfering with the project finish. In the critical path methods, the box shown in figure 6 is filled out for all activities.
	In order to calculate the critical path, you make a network diagram but with a box like the one shown in figure 4 for each activity. Then on a forward path the early start and finish date is calculated. The first activity starts on day one.		In order to calculate the critical path, you make a network diagram but with a box like the one shown in figure 4 for each activity. Then on a forward path the early start and finish date is calculated. The first activity starts on day one.
	*Early finish day is calculated by: Early start day + duration – 1		*Early finish day is calculated by: Early start day + duration – 1

S173891 at 11:03, 28 February 2021

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	== Importance of Lag and Lead ==		== Importance of Lag and Lead ==
	As a project is only temporary endeavor<ref name="PMBOK">Project Management Institute, Inc., ''Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE'', (Project Management Institute, Inc. (PMI). 6th Edition), Part 1 chapter 6</ref> therefore there is a start and a finish date. In most cases the finish date is decided in the process of planning a project. When the project starts it is the project managers job to keep the project on schedule and avoid any major delays. A project that is done well but not done on time can be viewed as a project management failure, as the project did not fail but the management made mistakes as the project was not done on time. In the ~~begin~~ of a project the project management team will make a schedule for the project. There are different parts that goes into the making of a schedule. The parts include:		As a project is only temporary endeavor<ref name="PMBOK">Project Management Institute, Inc., ''Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE'', (Project Management Institute, Inc. (PMI). 6th Edition), Part 1 chapter 6</ref> therefore there is a start and a finish date. In most cases the finish date is decided in the process of planning a project. When the project starts it is the project managers job to keep the project on schedule and avoid any major delays. A project that is done well but not done on time can be viewed as a project management failure, as the project did not fail but the management made mistakes as the project was not done on time. The Prince2 standart states ''"Plans provide the backbone of the management information required for any project; without a plan there can be no control."''<ref name="Prince2">Nigel Bennett, Robert Buttrick, Phil Stanton, Project Management: "Managing Successful Projects with PRINCE2'', (AXELOS Limited). 6th Edition 2017, Chapter 9), Part 1 chapter 6</ref> This states the importance of a plan that includes timeframe, what will deliver by who and how. Before the start of a project or in the beginning of the project management team will make a schedule for the project. There are different parts that goes into the making of a schedule. The parts include:
	# Planning the Management Schedule<ref name="PMBOK" />		# Planning the Management Schedule<ref name="PMBOK" />
	# Defining the activities<ref name="PMBOK" />		# Defining the activities<ref name="PMBOK" />
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	[[File:Lead.png\|thumb\|300px\|Figure 1. An illustration of Lead between two activities. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]		[[File:Lead.png\|thumb\|300px\|Figure 1. An illustration of Lead between two activities. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]
	During the project the project management team will control the schedule as well<ref name="PMBOK" /> . Lag and Lead is part of Sequencing Activities. In the process of Sequencing Activities, the relationship between the activities in the project are identified and documented. The benefits from the process are the definition of the logical sequence of work to obtain the greatest efficiency given all the project constrain <ref name="PMBOK" /> . All activities in the project should be connected to a least one predecessor and at least one successor expect the first and last activity. Activities should be connected to another activity with an appropriate logical relationship. These logical relationships must be designed so a realistic project schedule can be created. To help create and support a realistic project schedule Lag and Lead are used in between activities. Sequencing Activities will take the list of activities and turn them into a diagram to act as a first step to publish the schedule baseline<ref name="PMBOK" />
			During the project the project management team will control the schedule as well<ref name="PMBOK" /> . If the project is part of a program or a portfolio they might have developed a common way of planning a project and the project management should use this common way of planning<ref name="Prince2" />. Lag and Lead is part of Sequencing Activities. In the process of Sequencing Activities, the relationship between the activities in the project are identified and documented. The benefits from the process are the definition of the logical sequence of work to obtain the greatest efficiency given all the project constrain <ref name="PMBOK" /> . All activities in the project should be connected to a least one predecessor and at least one successor expect the first and last activity. Activities should be connected to another activity with an appropriate logical relationship. These logical relationships must be designed so a realistic project schedule can be created. To help create and support a realistic project schedule Lag and Lead are used in between activities. Sequencing Activities will take the list of activities and turn them into a diagram to act as a first step to publish the schedule baseline<ref name="PMBOK" />

S173891 at 19:14, 21 February 2021

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	=== Critical Path Method ===		=== Critical Path Method ===
	[[File:Critical_path_box.png\|thumb\|~~200px~~\|Figure 6. Activity box for the Critical Path Method. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]		[[File:Critical_path_box.png\|thumb\|300px\|Figure 6. Activity box for the Critical Path Method. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]
	After having done the network diagram the Critical path method can be used to identify the Critical path in a project. When identifying the critical path, the Lag and Lead are used. In the critical path the earliest start and finish day are calculated as well as the latest start and finish day and the float. The float is not to be confused with the Lag and Lead. Float is also known as slack, and it means the time an activity can be push without interfering with the project finish. In the critical path methods, the box shown in figure 6 is filled out for all activities.		After having done the network diagram the Critical path method can be used to identify the Critical path in a project. When identifying the critical path, the Lag and Lead are used. In the critical path the earliest start and finish day are calculated as well as the latest start and finish day and the float. The float is not to be confused with the Lag and Lead. Float is also known as slack, and it means the time an activity can be push without interfering with the project finish. In the critical path methods, the box shown in figure 6 is filled out for all activities.
	In order to calculate the critical path, you make a network diagram but with a box like the one shown in figure 4 for each activity. Then on a forward path the early start and finish date is calculated. The first activity starts on day one.		In order to calculate the critical path, you make a network diagram but with a box like the one shown in figure 4 for each activity. Then on a forward path the early start and finish date is calculated. The first activity starts on day one.

S173891 at 19:14, 21 February 2021

2021-02-21T19:14:09Z

← Older revision		Revision as of 19:14, 21 February 2021
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	=== Critical Path Method ===		=== Critical Path Method ===
	[[File:Critical_path_box.png\|thumb\|~~100px~~\|Figure 6. Activity box for the Critical Path Method. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]		[[File:Critical_path_box.png\|thumb\|200px\|Figure 6. Activity box for the Critical Path Method. Adapted from "Project Management: A Guide to the PROJECT MANAGEMENT BODY OF KNOWLEDGE"<ref name="PMBOK" />]]
	After having done the network diagram the Critical path method can be used to identify the Critical path in a project. When identifying the critical path, the Lag and Lead are used. In the critical path the earliest start and finish day are calculated as well as the latest start and finish day and the float. The float is not to be confused with the Lag and Lead. Float is also known as slack, and it means the time an activity can be push without interfering with the project finish. In the critical path methods, the box shown in figure 6 is filled out for all activities.		After having done the network diagram the Critical path method can be used to identify the Critical path in a project. When identifying the critical path, the Lag and Lead are used. In the critical path the earliest start and finish day are calculated as well as the latest start and finish day and the float. The float is not to be confused with the Lag and Lead. Float is also known as slack, and it means the time an activity can be push without interfering with the project finish. In the critical path methods, the box shown in figure 6 is filled out for all activities.
	In order to calculate the critical path, you make a network diagram but with a box like the one shown in figure 4 for each activity. Then on a forward path the early start and finish date is calculated. The first activity starts on day one.		In order to calculate the critical path, you make a network diagram but with a box like the one shown in figure 4 for each activity. Then on a forward path the early start and finish date is calculated. The first activity starts on day one.
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	== Limitations ==		== Limitations ==
	Lag and Lead is not a tool but a technique, there are limitation. Lag and Lead are more useful if use together with another tool, this could be the network diagram or the critical path methods as suggested in the article. There are also other scheduling methods where Lag and Lead are used. Another limitation can be that Lag and Lead can be hard to identify at the beginning of the project and therefore they have to be adjusted during the project. It can also be hard for the project manager alone to identify all the Lag and Lead, that means that if the project manager alone is reasonable for the Lag and Lead the estimate will be more off than if the estimates are made with the project management team and with input from the project team. Activities can have Lag and Lead with different types of relationships, however as stated the Finish-to-start is the most used one. A Start-to-finish relationship can in most cases be change to a finish-to-start as the defining activity is swapped. This is not a limitation, but this has caused confusion and lead some sources online to say that two activities with a lead can only have a Finish-to-start relationship. However, it depends on which activities are depending on what other activities. On figure 7 two examples of the dependency can be seen. If activity B is more depend on activity E than the other way around the relationship will be Finish-to-start if the activities are sequences as shown on figure 7(Example 1). If activity E is more depended on activity B the relationship will be Start-to-Finish if the sequences are as shown on figure 7(Example 2). There a project management team should keep an overview of which activities are depending on what.		Lag and Lead is not a tool but a technique, there are limitation. Lag and Lead are more useful if use together with another tool, this could be the network diagram or the critical path methods as suggested in the article. There are also other scheduling methods where Lag and Lead are used. Another limitation can be that Lag and Lead can be hard to identify at the beginning of the project and therefore they have to be adjusted during the project. It can also be hard for the project manager alone to identify all the Lag and Lead, that means that if the project manager alone is reasonable for the Lag and Lead the estimate will be more off than if the estimates are made with the project management team and with input from the project team. Activities can have Lag and Lead with different types of relationships, however as stated the Finish-to-start is the most used one. A Start-to-finish relationship can in most cases be change to a finish-to-start as the defining activity is swapped. This is not a limitation, but this has caused confusion and lead some sources online to say that two activities with a lead can only have a Finish-to-start relationship. However, it depends on which activities are depending on what other activities. On figure 7 two examples of the dependency can be seen. If activity B is more depend on activity E than the other way around the relationship will be Finish-to-start if the activities are sequences as shown on figure 7(Example 1). If activity E is more depended on activity B the relationship will be Start-to-Finish if the sequences are as shown on figure 7(Example 2). There a project management team should keep an overview of which activities are depending on what.
	[[File:Lead_relationship.png\|thumb\|center\|~~600px~~\|Figure 7. Examples of two types of Lead relationships in a sequence.]]		[[File:Lead_relationship.png\|thumb\|center\|400px\|Figure 7. Examples of two types of Lead relationships in a sequence.]]

	== References ==		== References ==
	<references />		<references />