Today AA claims an estimated 2.1 million members worldwide, with 1.3 million of them U.S. residents. Almost 100,000 members reside in Canada, and more than 700,000 can be found in other countries, from Uganda to Sweden to Yemen. Some of the members in those 150-plus nations are affiliated with groups; others who live in places where they've been unable to form collectives are dubbed "loners." Sometimes members start as loners (there are currently 157) and then form local groups — a move common in U.S. military stations overseas, according to AA. And tens of thousands of members enter the program from inside correctional facilities. The program, historians have noted, is based on the notion that what really matters is not who you are or where you are but what you are; only an alcoholic can understand and help another.