Six Sigma, Lean, Rupp, Scrum, SDLC and moreā€¦ how do you pick the right methodology for your organization?

Question from the Gartner Symposium Forums

In my experience, there is no “one true and only” methodology, model or framework. Of course, the problem then becomes that people become religious zealots rallying around “their” methodology. What’s really needed is a group that gathers the information, facilitates the sharing of best practices (regardless of the methodology) and helps the groups to realize how the methodologies and models can complement one another. Also, this can help to understand and where each methodology is most appropriate and effective. A similar discussion regularly comes up around ITIL, ISO 9K, CMM, CoBIT, TQM, etc.