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Setting Tasks Constraints

Viewpath Support -

Video: Constraints and Constraint Dates


What Are Constraints?

In project planning, "constraints" are used to help a project manager easily identify tasks that are on a non-negotiable schedule (e.g. tasks that cannot start earlier than a specific date or must finish on a certain date).

Viewpath allows you to lock-in task dates using the "Constraint" and the "Constraint Date" fields. You can access these fields within the New Task or Edit Task dialog boxes by clicking on the "Advanced" tab or you can add them as columns in your Tasks List view.

Types of Constraints

There are eight types of constraints:

  1. ASAP: As Soon As Possible
  2. ALAP: As Late As Possible
  3. SNET: Start No Later Than*
  4. FNET: Finish No Earlier Than*
  5. SNLT: Start No Later Than*
  6. FNLT: Finish No Later Than*
  7. MSO: Must Start On*
  8. MFO: Must Finish On*

*Must be used in conjunction with the Constraint Date column.

When you apply a constraint, an icon is added to the Gantt Chart as a visual indicator that there is a constraint.

For Example...

Let's say that you have a task that has a drop-dead date for completion. That is, the task Must Finish On (MFO) a specific date. After creating the task:

  • Add the Constraint and Constraint Date Columns
  • Change the Constraint type to "MFO" (Must Finish On)
  • In the Constraint Date field, enter the date on which the task must be completed

From this point forward, the Viewpath application will not allow you to alter that task in such a way that the Finish Date is different from the date that you defined in the Constraint Date field.

Backward Scheduling

Let's say that you know when a project needs to finish but you need to calculate the start dates for preceding tasks. 

  • Assign the correct MFO Constraint Date to your last task
  • Assign the constraint ALAP (As Late As Possible) to the preceding tasks
  • Link all the tasks together

The "ALAP" tasks will be be based on the MFO Constraint Date and will adjust accordingly as in the image below. 


 Give It a Go!

We invite you to play with the Constraints options. Remember that you also have three ways to Link tasks together using the Link menu. 

If you make a mistake, no worries! Simply use the Undo button as often as you need!



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