Author: John Reinheimer

John Reinheimer, PMP, PMI-SP, MCP, has been using Project for 18-plus years. He has worked as a scheduler, project manager, trainer, and PMO developer at several companies, including DirecTV, Mattel, Boeing, Blue Cross Blue Shield of Florida, and Fidelity Information Services. John is an independent consultant currently working with the United States Navy on a $1.7 billion unmanned vehicle program. Contact him at

Understanding Task Types: Don’t Get Frustrated!

The sophistication of Microsoft Project can sometimes lead to confusion among users, especially when it comes to understanding task types. This guide aims to break down the task types in Microsoft Project and provide a clear understanding of how to use them effectively in managing your projects. For each task in your project, you must set three task type choices: Understanding Task Types in Microsoft Project To understand these, you have to learn the underlying formula used by the scheduling engine: Duration * Units = Work Before I explain each aspect of the formula, please note that with this formula, as you change any given component, that will change the other components too. For any tasks, you can choose which piece of the equation Project will calculate by setting the task type. Regarding work, there are some tasks that you can add more resources to and the task’s duration will decrease. This is called effort-driven scheduling, which is Project’s default. The duration of a task will shrink or grow as resources are added or removed, while the amount of total effort expended on that task stays the same. For example if you have a week long task to test several units, you can decrease the amount of duration by adding more testers. For other tasks, adding resources won’t decrease the duration, such as training. No matter how many instructors one assigns to a three-day training course, it will still take three days. Another example is backing up a computer. One person or 10 can back up a computer — it will still take the same amount of time. Effort-driven scheduling only occurs if you keep this option clicked in the Task Information dialog and you add or remove resources from a task. (Keep in mind that when you add resources to a task, this does cause some increase to the task’s duration due to increased communication needs between the resources.) Here are the steps for selecting a task type for one or more tasks in Project: Use the Task type: drop-down menu to select the appropriate task type. Select the Effort Driven checkbox if desired. Note! Most of the time I leave “Effort-driven” unchecked. As I stated earlier, you must set your task to be one of three types. So how do you know which one to use? Here are some guidelines. Fixed Units Tasks Fixed unit tasks means that in the formula Duration * Units = Work the units are fixed. Use Fixed Unit tasks in situations such as: Here are afew tips about this type of task: Fixed Work Tasks Fixed work tasks means that in the formula Duration * Units = Work the work is fixed. Use Fixed Work tasks in situations such as: Fixed Duration Tasks Fixed duration tasks means that in the formula Duration * Units = Work the duration is fixed. Use Fixed Duration tasks in situations such as: There are two simple guidelines to remember when determining task types. If you remember these guidelines, you’ll be able to predict howMicrosoft Project will respondas you enter duration, units, and/or work. Guideline #1: Enter the duration estimate or work estimate and fix that number by setting the Task Type accordingly. Fixing it prevents Project from changing it. If you enter a Duration estimate, set the Task Type to Fixed Duration. If you enter a Work estimate, set the Task Type to Fixed Work. Guideline #2: Provide the second value in the formula Duration * Units = Work and let Project calculate the third value. If you created a fixed duration task, assign the resources you need and let Project calculate the work. If you created a fixed work task, assign the resources and let duration be calculated. If you entered the duration and work, Project only needs to know who will do the task and it will calculate the number of resources needed (units). Note! Always provide only two of the three values in the formula. Here’s a chart you can print and stick next to your laptop until it becomes second nature to you: As a general rule the priority of which variable will most likely change is duration, then work, and then units. If you can master the concept of task types, you’ll be well on your way to fully understanding how Project works and how to use its capabilities to your best advantage — and your frustrations will diminish. Related Content Webinars (watch for free now!): Digging Deeper – Learning More about Task Types Eliminate the Confusion – Deep Dive into Task Types and Effort Driven Articles: Do’s and Don’ts: Using Hammock Tasks 3 Task Tips