Who they are
Surveys in Western countries find convert Buddhists are, on average, better educated and wealthier than the general population, and come disproportionately from the professions. Many were brought up in another religion or none. Most came through meditation rather than through belief, and many do not call themselves Buddhists at all.
What they practise
Meditation, retreats, reading, a teacher if one is available, and ethics worked out rather than inherited. Ordination is rare. Rebirth and merit are often held loosely or set aside, which traditional teachers sometimes regard as taking the useful part and leaving the rest.
Convert communities have had to build from nothing: no temple, no funeral rites, no calendar, no grandmother who knows how this is done. Some have borrowed heavily from Asian forms, some have invented, and the results vary.
Honest difficulties
Western Buddhist communities have been criticised from inside for being far whiter and more affluent than the cities around them, and for a string of abuses of authority by teachers in the 1980s and 1990s that the communities were badly equipped to handle. Both have produced real change: guidelines on teacher conduct, lay boards, and groups led by and for people the mainstream centres were not reaching.
Why it matters
Buddhism is now also chosen, not only inherited.
History and tradition
What historians can say
Documented by sociological survey work and by the communities themselves. The honest summary is that convert Buddhism is young, roughly two generations old in most countries, and still deciding what it is.