This article examines two disputes within sex and gender movements, us
ing them to think through inclusion/exclusion processes, the place of
such explosions in the construction of collective identity, and the ge
ndered nature of social movements. Literatures on collective identity
emphasize the ways boundary negotiation reinforces the solidarity nece
ssary for collective action and note benefits of solid boundaries, yet
downplay the role of internal conflict in the making of collective id
entities, The cases examined here both involved the explicit expulsion
of some ''members'': the North American Man/Boy Love Association from
the International Lesbian and Gay Association, and transsexuals from
the Michigan Womyn's Music Festival. An incongruence between practical
participation and symbolic exclusion suggests that internal movement
debates are best understood as public communications, depending heavil
y on the communicative environment. Finally, these stories raise quest
ions about the gendered nature of collective identity construction in
social movements more generally.