A "Workback Workflow" is a type of Dynamic Duration workflow where instead of all task dates calculated and flowing forward from the project start date, they all calculate and flow backward from the project end date. This is great for events and other projects where you need to hit a specific target date and want all task dates to be automatically calculated/shifted/updated so that you’ll always hit that target.

To create and use a Workback Workflow, you'll follow basically the same set of steps for creating a Dynamic Duration template, and then projects from that template, as outlined here:

There are two crucial differences from the article above for Workback Workflows:
  1. In Step 3 of "Create Your Workflow Template", when you select the project to use as the template, you'll see there is a new checkbox below it labeled This is a Workback workflow. Be sure to check that checkbox.
  2. In Step 2 of "Use Your Template", instead of filling in a project start and due date, you'll only enter a project due date. This is the key ending date which everything will calculate back from. Flowsana will assign this ending date as the due date for the bottom task in the project, and it will work up from there.
Additionally, there is a key principle that needs to be followed for workback workflows: there must be a consistent, unbroken line of dependencies from the last task in the project backward. Any task which is not part of a dependency chain working back from the last task will not be assigned a date.

Also, you can still use lag times in a Workback Workflow. However, conceptually they work a bit differently: if you want to build in a gap between the end of a task and the start of its dependent task (the task following and blocked by it), put the lag time on the blocking task and use a negative number for the Lag Time.