Task dependencies represent the order in which tasks must be performed. Dependencies enable you to work out the optimal task order, providing the fastest route through the project. There are 4 types of dependency relationships. A task can have multiple successors or multiple predecessors.
The impact of getting a dependency wrong usually results in delays. It's important to monitor dependencies throughout the project and communicate them to the project team.
Start-to-start
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Predecessor must start before successor can start. This relationship allows the Project Manager to run tasks in parallel.
Start-to-finish
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Predecessor must start before Successor can finish
Finish-to-start
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Predecessor must finish before Successor can start. This is the most commonly used dependency.
Finish-to-finish
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Predecessor must finish before Successor can finish