Despite constituting only a small fraction of all psychiatrists, psychoanalysts rose to a position of dominance within American psychiatry in the post-World War Two era. This article explains their success. A review of the social and institutional context of psychoanalysis and psychiatry reveals that many factors were actually unfavorable to psychoanalysis, and several others were at best equivocal in their support of analysis. Neither income, status, the relationship between institutions and ideology, or other such factors accounts for the success. After describing these factors and showing how they do not work as explanations, I argue that psychoanalysis succeeded largely because of its utility to the psychiatric profession in the growing jurisdictional disputes with non-medical competitors, specifically clinical psychology.