The author briefly reviews the literature on the relationship between obsessional neurosis and manic-depressive psychosis. Features seen to be similar are: a phasic recurrence with symptom-free intervals, the frequent mutual appearance of obsessive and depressive qualities, a high degree of ambivalence, and a common relation to anal-sadistic libidinal organization. Toker describes the case of a twenty-five-year-old woman with recurrent episodes of severe obsessional thoughts subsequently replaced by depressive features. He sees this as a case of underlying manic-depressive psychosis initially masked by obsessive-compulsive symptoms. The accuracy of his diagnosis of psychosis and of the implications he draws for electroshock therapy are questionable.