It's a little known fact that Rational's tools are equally at home in an agile development process as well as other, more "heavyweight" process structures.
Now, IBM's Scott Ambler has written an article in Dr. Dobb's January newsletter on Agile development. The article focuses on best practices for governing development projects and highlights the eighteen practices of the Lean Development Governance Framework created by Ambler and IBM's Per Kroll.
It's an interesting read. You can find the article here: http://www.ddj.com/architect/205920564