Constraints in Project Professional

Restrictive constraints are to be avoided, most of the time, because they limit the ability of project to schedule your work. Constraints can cause confusion when trying to determine why dates do not align to expectations. In some cases constraints are necessary or even recommended, what is important is that you know you are using them.

  

If you don't think that you add constraints to your project plans you could be doing so and not even realize it. Whenever you alter a planned date manually by changing the date instead of adding lag or lead time, altering predecessors or changing durations you are adding a constraint.

“If you manually enter a start date or a finish date for a task, Project changes the constraint type for that task to Start No Earlier Than (SNET) or Finish No Earlier Than (FNET). These semi-flexible constraint types force the task to start or end on the specified date regardless of subsequent changes that would otherwise affect the task's place in the overall project plan.”

–Microsoft Office Online Article

There are many different types of constraints in Microsoft Project. The table below details these:

Understanding what the constraints do to the scheduling engine you can now infer some circumstances where a restrictive constraint may be necessary. Listed below are some instances where having a restrictive constraint may be a good idea:

· When you have no choice in the matter and a specific task needs to occur on that date

· Although deadlines can also be used here, it is understood that some tasks such as onsite work need to occur on a specific date once scheduled with the customer

· When you are trying to schedule tasks differently than the default method project utilizes.

· Project schedules tasks as soon as possible by default.

· There may be instances where you want to schedule tasks as late as possible or using any of the other constraint types in specific situations.

If you already have constraints in your project schedule you can remove them with a bit of work. Here are some steps to remove constraints from your plan and allow the scheduling engine to work for you.

1. Look for the constraint symbol in the first column of your task
2. Double click on the task to go into task information
3. Click on the advanced tab
4. Change the constraint type to read as soon as possible
5. Now go into your plan and adjust the predecessors/lag/lead times to allow project to schedule your work how you expect it to be scheduled