I was having knee pain from running. A very knowledgeable local store, recommended as one of the best in Boston, turned me on to these shoes. (Don't worry, I bought my first pair from them to support them.) They provide excellent shock absorption, which helps your knees for obvious reason. Less obvious is that these shoes provide excellent support for your ankles, which in turn puts less stress on your knees.

I used to have to stop running because of leg pain. Now I have to stop because I'm about to go into cardiac arrest. That's how it should be!