Task predecessors [in-depth guide]
Guide contents: General questions | The basics | Negative & positive lag | Concurrent & triggering multiple tasks | Summary task level predecessors | Cross project predecessors | Resources
This guide is designed to give you further insight into managing project schedules by utilizing task predecessors.
General questions
What is a "predecessor" in Workamajig?
A predecessor is a term used for the linking of tasks within a project schedule.
Should I be using predecessors?
Yes, if you have tasks that occur one after the other, then using a predecessor will enable features in the schedule and elsewhere in the system that follows this design. It can prevent users from viewing tasks (Today page display options & view filters) or working on tasks while the previous task is not yet complete (security right enabled). These also allow you to run reports to show which task is the current open task in the schedule.
What if I have a task that relies on multiple tasks being done first?
No worries, you can have multiple predecessors for one task. Then ALL linked tasks need to be done first, before starting on this one task.
What is the difference between the Link task button vs. the Add predecessor button?
No difference in the final result, just a different interface. The Link task button connects tasks you have highlighted in the order you highlight them in the schedule grid. When you go to Add predecessor, you are then presented with a list of ALL tasks on the schedule with a checkbox next to each and you then choose which.
The basics
How to link all tasks in order
- Click the top checkbox next to the task rows.
- Choose the Link option. NOTE: You may want to Unlink first if there are predecessors already in place you don't want.
- All the tasks are now linked as predecessors from the top down.
How to adjust a single tasks predecessor
- Click on the task in question.
- In the task details panel to the right, look for predecessors.
- In here you can click Add a predecessor for this task.
Negative & positive lag
There are two common scenarios in which to use lag:
Same day tasks
- When you have multiple one-day tasks that are to occur in order, yet you want to plan for them to take place on the same day. Then you can link them together, then in the predecessor line in the details, there is a column to the right called Lag. Enter the value of negative one (-1).
Client feedback tasks
- When you have a delay in the schedule, where no work is being performed. Yet you want a trigger to start a task a few days after the previous task, then positive lag may be the way to go. For example, if site testing is done and it's now in the client's hands. So you may have a task called client review. In this case, make the client review task for one day in duration, but add a lag of say two days (2). Then the client review task won't start or trigger until two days after the internal review task was done.
- This may be a larger discussion, however a big reason why you do not want client review to be a 3-day duration task is that Workamajig goes based on the plan start date of a task, not the plan completion date. So if the task doesn't actually start until 3 days after what you planned, then the due date of that task and all subsequent tasks will get pushed out 3 days as well.
Concurrent & triggering multiple tasks
If in the middle of your schedule you have two or more tasks that run concurrently, you can use the predecessor features in several ways to accomplish this. This section will focus on a linear timeline, read below for the alternative to summary task-level predecessors.
NOTE: If you have no predecessors, then all tasks in the schedule will plan to start at the same time.
If you want one task when completed to trigger other tasks to start, this can be achieved with the following:
- With a task already in the schedule (say it's called concept), and you want that task to trigger two other tasks (say copy & design), then in those two tasks, link them both to the first task.
If you want one task to be reliant on starting only after multiple tasks have been completed, then try the following:
- In the one task (say internal review), go into the Predecessors tab and choose the multiple tasks (say copy & design) as its predecessors that it is to rely on.
Summary task level predecessors
You can achieve the same results as above using summary tasks and predecessors, however, using summary tasks does open up your project schedules for more advanced techniques.
With the addition of the summary task, you can have the predecessor set at the summary level. What this does is trigger tasks under the summary task to start when the predecessor task is done.
Ex. 1: In the above screenshot, task 2.1: copy does not have a predecessor set. By default, the task accepts the predecessor set on the summary task>task 2: production, which is triggered to begin at the completion of task 1: setup
Ex. 2: The summary task>task 3: review, is triggered by the completion of summary task>task2:production. This setting means all detailed tasks under task 2: production must be completed for task 3: review 1 to begin. This allows you to add or remove detailed tasks under task 2: production without affecting this connection. Ex. adding in a photo shoot step will extend the time needed to finish production, and the start of review 1 will automatically be "pushed out" by that addition.
Using the summary task as the trigger for the next set of tasks allows you to also add new groups of tasks from templates, other projects or by copying a current group of tasks, such as adding another review round. You can then set up the connection between the summary tasks and reset the connection to the original trailing task. Ex. add a review 3>>set predecessor for review 3 to review 2> edit connection of prep delivery, changing the setting from review 2 to review 3.
Click here to see the full Cross-project predecessors [in-depth guide]
Resources
Project manager overview [guide]