Synopsis This article explores the social and political implications of transgenderism for women's groups and organisations. One aim of transgender support groups such as, The Gender Centre Inc. and others, is the right of male to female transgenders (MTFs) to enter what were previously understood to be women-only spaces such as women's health centres, domestic violence shelters, and rape crisis centres. MTFs whether pre or post-operative, claim the right to enter these spaces as both clients and workers. In-depth interviews were conducted with managers of gendered spaces and a small number of workers. Discussions centred around their values and policies about gendered spaces and the advantages and disadvantages of having women-only spaces, as well as their experience of trans-inclusion when it had occurred and the impact on staff and clients of inclusion. The majority of interviewees supported women-only space and employed only female staff in their centres. Their policy and practices around the employment of MTFs, or accepting MTFs as clients, depended on whether or not they considered MTFs to be women, a point upon which there was significant disagreement. Those who believed MTFs to be women supported their inclusion. Those who did not consider MTFs to be women felt that their presence would compromise women's feelings of safety and threaten not only the very existence of women-only spaces, but also they services they provide.