The case described is that of a man raised in the Vietnamese peasant countryside who clearly fits the transsexual syndrome. On physical examination he appears to be a normal male, yet he insists that he is a female. He dresses as a woman and is able to successfully "pass" in society. He relates that he felt he was a female from earliest childhood. He prefers nonhomosexual men, denies any heterosexual experience, and has an all-consuming desire for the sexual transformation operation. This paper focuses on the social aspect of transsexualism and the manner a society, particularly the Vietnamese, may handle transsexual behavior.  These ways can be seen to fall into a continuum. On one end, sexual role reversal is institutionalized and transsexual-like behavior is carried on according to a prescribed cultural pattern. The Vietnamese "hermaphroditic witch" could be included in this category. In the middle of the continuum, the idiosyncratic transsexual is provided an acceptable cultural role, and he therefore should be visible when he occurs. The Vietnamese young person who cross-dresses could perhaps be in this category. On the other extreme, the transsexual role is not conceivable or, at best, is very marginal. Here, the transsexual remains hidden in the general culture and can only be detected, as the person described in this paper, by accident.(EUiott M. Heiman, M.D, and Cao Van Le, M.D)