I have been a guest member of the Henley Knowledge Management Forum since its inception over ten years ago.
They do some great collaborative research through their working groups, hold several 1-day seminars each year and a two-day conference which is coming up on 16-17 February that is open to non-KM Forum members.
What has long disappointed me is that most of their papers are only available to forum members and are not freely available on the web which means I cannot blog or tweet them. But this is starting to change and they have made a number of Knowledge in Action Leaflets available. These leaflets are only a few pages long but summarise the findings of some of their more interesting collaborative research projects. Well worth taking a look.