Interesting question on LinkedIn:

What is the difference between an approach and a methodology?

What is the difference between an approach and a methodology?
Is it true that approach is just an idea and is less proven while methodology would normally start as an approach but is eventually time tested and proven? What takes an approach to convert into a methodology?

Here was my response:

I think of an approach as the foundation, or underlying principles that guide you in how you get your work done. I'm an agile software development proponent, and I strongly support the approach/philosophy expressed in the agile manifesto (http://www.agilemanifesto.org).

Methodologies, to me, prescribe more detailed steps to take to accomplish goals. Scrum is, in essence, an agile approach (the mantra is "inspect and adapt"), but it gets applied in many instances as a methodology (Though shalt provide a burn-down chart).

Methodologies excuse people from thinking about underlying principles. If you follow the rules for making a burndown chart, your methodology has been followed, but if you are avoiding opportunities to gain greater insight by taking a different tack, you are avoiding the approach/principles.

An analogy to cooking - using a methodology is like following a recipe - with your measuring spoons/cups at hand, precise temperature measurements, etc. Using an approach/principle requires more understanding of the ideas... the fact that sauteeing onions releases liquid gives you some information that allows you to adjust to other aspects of your cooking (like don't try to brown your meat while sweating your onions, because the released liquid will cause your meat to steam instead of brown).

In sum, I would say an approach requires more thinking and adapting, while a methodology provides more training wheels to give you procedures that you may not be able to link to the underlying approach/principles. I think that beginners require methodologies (like beginning cooks require recipes) while experienced folks can apply fundamental principles based on sound judgment (like experienced cooks simply press down on the steak to assess doneness instead of measuring the time).