CAMRA was the first example (as far as I am aware) of a non-pressure group. :-)

I will say that one measure of their success - despite the anoraks and tickers - is the glorious city of Edinburgh. When I was first up there there were two or three bars ONLY that sold real ale> One was the Diggers and I forget the others.

Now of course the vast majority of Edinburgh pubs seem to serve real ale.

Mind before you go rushing up there, you do need a sense of humour to drink there.