I have been trying to understand the PMBOK table 3-1 (5th edition) Project Management Process Group and Knowledge Area Mapping, and I find its orientation very strange. The book covers the table in a horizontal fashion focusing on Knowledge Areas for each Process Groups.

I find it awkward and my instinct want’s to focus on the Process Group and the Knowledge Area required per that Group.

Is there a particular reason why the book is in the order of “Knowledge Areas” not the Process Groups?