The authors describe in detail the case of a man hospitalized for a severe depression fifteen months after a 'sex conversion' operation. They refer to Stoller's description of a specific family constellation in male transsexualism in which the mothers are bisexual, empty, depressed, excessively permissive, and have a tendency to keep their infants close to their bodies too long. The fathers are passive and distant. In this setting a strong unambivalent mother-child symbiosis develops, producing a feminine core gender identity. In the authors' case much of the same pattern obtained, with disturbances of pregenitality leaving the patient unable to cope adequately with the Oedipal and later stages of development. They stress the increasingly regressive ego and psychosexual attempts at solution culminating in the surgical procedure.