The definition I go by is that Agile is a set of software engineering practices. Then there is Scrum. Scrum is not a methodology either - even though some people call it that. It is a process framework for product management.

Definitions aside, you bring up a great question of how PMBOK and Agile/Scrum work together. As a consultant in a large corporation (that live by processes), I have some experience in using Agile as you talked about, IE, inside the parameters of a parent/existing processes - such as initiation, change-control etc. I have experience in implementing Scrum (ScrumButt) and defining these boundaries in a medium sized organization. I got away without making the PMO too mad at me! It is a a struggle but we can make it work.

As Agile/Scrum becoming main stream, I am seeing efforts that started documenting this aspect. One book I know of is by Michele Sliger titled “Software Project Manager’s bridge to Agility”. I have heard good things about this book, yet to pick one up.

Enjoyed your blog!
Manoj PMP, CSM, CSP