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Introducing Lead & Lag in Task Dependencies

SakshiMunjal's avatar
SakshiMunjal
Icon for Microsoft rankMicrosoft
Jan 24, 2024

Welcome to 2024! As you kick off the new year with renewed momentum for your projects, here are some new features in Microsoft Project for the web* that can help you enhance execution. 

 

As you and your teams power through tasks in your plans and projects, you might have on your wish list the ability to get a head start on the next task or introduce a delay? You can now set advancements and delays to your task dependencies to fine-tune your project timelines. 

Lead times provide a head start to the consecutive event, allowing for a buffer before the dependent task begins. On the other hand, lag times introduce a delay between consecutive events, creating a gap or waiting period before the next task can start.  

 

You can add the lead or lag through the Grid and the Task pane in days, hours, minutes, weeks or months. It also automatically gets updated in the Timeline view. For a detailed overview, hover over the dependency link in the Timeline view. 

  

Demo of how Lead Lag can be added through the Grid, Pane and Timeline View

 

Keyboard shortcodes are also supported, like in Project Desktop in the grid view. You can add your dependency with lead or lag by inserting: 

[Task Number][Dependency Type (FS/SF/FF/SS)] +/-  [Lead/Lag numeral][Duration Format] 

Example: 3FS+10d 

Here, a finish to start dependency has been established with a lag of 10 days. 

 

*The above functionality is available to you in Project for the web. In November 2023 at Ignite , we announced the new Microsoft Planner, bringing together to-dos, tasks, plans and projects into a single unified experience. The features you know and love in Microsoft Project for the web will be available, in the new Planner app in Microsoft Teams in early 2024 and later in 2024, in the Planner web app. Learn more about the announcement at aka.ms/thenewplanner 

 

FAQs: 

Which license users will be able to use lead-lag? 

All users will be able to view lead-lag and all users with Plan 3 or greater license will be able to add and edit lead-lag to their projects.  

 

Will importing an MPP from the Project desktop to Project for the web preserve lead-lag? 

Yes, the import from the MPP option in Project for the web will allow the import of buffer/delay between tasks along with the dependencies from the original project into Project for the web. 

 

Will the exported excel have information of lead-lag? 

Yes, the exported excel will preserve lead-lag. 

 

How do I know which dependency to use when? 

You can learn more here Advanced Task Dependencies in Project for the web - Microsoft Community Hub. 

Updated Feb 07, 2024
Version 2.0
  • hendrikl's avatar
    hendrikl
    Copper Contributor

    The finish-to-finish dependency type doesn't work as expected. Did anybody else observe this?

  • daibt's avatar
    daibt
    Brass Contributor

    I'm still eagerly waiting for this feature to be released. Do you have any idea when it will be available?

  • kblarsen's avatar
    kblarsen
    Copper Contributor

    Have been waiting for this feature for so long.

     

    When having a single task or milestone driven by two or more Start to Finish dependencies the dependant task is driven but newest date.

     

    That seems not to be logical, would think it should be the oldest date.

     

    A exampel is that you have a number of task and what to order something for these task with a lead time, but only want to order once.

     

    When it is a Finish to Start task is should the newest.

     

     

     

  • Thank you for taking the time to provide your feedback Kelvin_Kirby . We appreciate your input. The term 'buffer' was intended to signify a 'time buffer between tasks'. In order to avoid any confusion with the Task Buffer, we have edited the text. Thank you once again for your feedback.

  • Kelvin_Kirby's avatar
    Kelvin_Kirby
    Brass Contributor

    Oh dear!  This is another example of someone posting an article without a fundamental understanding of concepts. Lets be clear - Lead and Lag times are NOT Buffers. Buffers are an entirely different thing. Lead and Lags are part of dependencies and reflect the nature of the relationship between two dates associated with different tasks (not always in the same project plan either).  This article simply confuses the less experienced allowing them to use incorrect terminology in project management. 

    In brief lets try and clarify the terms for the benefit of the less experienced 

    • Lead Time: Allows overlap and schedules a task to start before its predecessor finishes, effectively pulling tasks closer together to shorten the project duration.
    • Lag Time: Introduces a delay between tasks, ensuring that there is a necessary gap for tasks that cannot immediately follow one another, for example waiting for paint to dry or for concrete to set (which by the way would be elapsed duration lags, since these are real time lags and not dependent on calendars). 
    • Buffers: Adds extra time to tasks or project phases as a safeguard against uncertainty and risk, ensuring that the project has flexibility to deal with unexpected events without derailing the overall timeline. Often buffers are elastic in nature since the buffer time may be consumed and reduced depending upon the status of the tasks and then project. Whilst lead and lag times are typically static periods (although do not have to be - that's dependent upon the capabilities of the software), buffers typically reduce in available time during the lifecycle of the project to the point where ultimately the buffer time can reach zero (although not desirable of course, and typically adjusted interactively by a PM during the project lifecycle). Critical Chain Management uses buffers to good effect in manufacturing concpets. 


    In the desktop version of Microsoft Project buffers have NEVER been a feature or capability and required a third party product (typically) to model Critical Chain Management in Microsoft Project.  In fact in Microsoft Project today (Planner) they still are not a feature and this article is extremely misleading. 

    And of course, lead, lag and buffers are not to be confusd with constraints which are themseleves a different concept, although applying lead and lags may cause contraints to be applied. Constraints are a property of a date (start or finish) of a task - for example a task may still have a lag applied but is still scheduled ASAP (e.g. no constraint). 

    Hopefully, going forward, Microsoft will ensure correct use of terminology in such articles - thereby avoiding the inevitable confusion imposed by them on users!! 

     

     

  • Yann-78's avatar
    Yann-78
    Copper Contributor

    finally! This was a must to have feature. Once the 6 date constraints are implemented I’ll be able to use this tool for my simple projects.