Dependency Types in Project Management refer to the relationship between project tasks, including what tasks must be completed before or after another one can take place. Dependencies can be either external or internal; external dependencies involve outside influences like vendors, while internal dependencies are those within the organization’s control. In either case, it is important for Project Managers to identify and document such dependencies to ensure a project runs smoothly. By doing so, they can more effectively plan and manage resources, as well as minimize obstacles that could prevent completion of the project on time.