Comprehensive Project Management and Scheduling Techniques for Students Practice Test

The main idea here is whose work drives the sequencing. External dependencies are tasks that rely on work outside the project team, meaning you must wait for another organization, supplier, regulator, or customer to complete something before your project can proceed. Internal dependencies are tasks that rely on work within the project itself, so the project team controls the sequence and must finish one activity before the next can start.

For example, finishing the architectural design before construction starts is an internal dependency because both tasks are within the same project. Needing a permit from a city agency before starting construction is an external dependency because the external party’s action governs when you can begin.

External dependencies introduce external risk and often require contract management, supplier coordination, or stakeholder negotiations, while internal dependencies are managed through internal planning and resource scheduling.

The idea that external dependencies involve work inside the project and internal dependencies occur outside is the opposite of the truth, and saying they’re the same ignores the separate sources of control and risk. Saying external dependencies are always optimistic isn’t accurate, since they can lead to delays depending on the external party’s timing.