QUESTION
What are the reasons why a project manager should select PMP certification rather than Prince 2, or vice versa? Are they complementary or competing?
ANSWER
I've got them both and can tell that they are competing. The biggest difference I found is the role of project management. In PMP the PM is responsible for the result of a project. If something goes wrong - blame the PM. If the project is behind the schedule or overruns its budget - blame the PM. That's the fundamental rule of PMBOK. (and I totally agree with it).
In PRINCE2 the PM is a middleman between the project and its control board. If something goes wrong the PM has to raise the problem to the board (upper management). Then they make a decision and return it back to PM for execution.
In any case I would recommend to pass them both for your portfolio and your self-education.
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