The author contends that all depressions have much more in common than they do in differences. He postulates that many depressions rest on an event, either near or far in time, which brings home to the victim the futility of striving. Such striving is derived from an effort, at an early age, to please parental figures and has been incorporated as a significant element in character formation. The difference between reactive and endogenous depressions rests in the relative degree of immediacy of the provocative factor. The relative effectiveness of electroshock in endogenous, as opposed to reactive, depression does not invalidate this thesis. Treatment of all depressions rests, primarily, on the one best known item of the natural history of depression, namely, its natural recover-ability. With this as a basis, psychotherapy is helpful in ridding the patient of the guilt associated with his inability to strive towards those goals which have always guaranteed his self-approbation. This furnishes a foundation for mental hygiene for the patient after the recovery period is achieved.