Two cases of psychosis associated with oral and intravenous abuse of methylphenidate are reported. Most elements of the classic folie à deux are seen in their identical paranoid delusions. The wife initiated the original delusions and was the controlling force by her helpless and childlike, but strongly demanding behavior. The husband, though having highly defended dependency needs, was not strictly passive or submissive in the relationship. Hostility over unmet needs and demands by the other partner appeared to be increasing rapidly just prior to the onset of delusions. In contrast to most reported cases, identification was found to be a mutual process. Folie à deux occurring in the absence of a functional psychosis in one partner has not been previously reported.