What is the definitive guide to project management methodologies according to Bill Carmody?

According to Bill Carmody, the Project Management Body of Knowledge (PMBOK), published by the Project Management Institute (PMI) in the United States, is widely accepted as the most authoritative and comprehensive project management methodology.

PMBOK, along with PMI’s related practice standards, forms a full-fledged framework that many professionals treat as the definitive guide to project management worldwide.

Are you asking because you are considering a certification, or are you looking for a methodology to use on a specific project?