Physicians and patients frequently assume a causal connection between life events and subsequent episodes of psychiatric illness. It seems to ‘make sense’ that an illness which is to some extent manifested by disordered emotions could be caused in part by emotion-producing events. But plausibility alone is no proof of the truth of such an assumption. Realizing this, several investigators have conducted systematic studies of the interrelationships of life events and illnesses, both psychiatric and medical. Such work has been reported by Adamson and Schmale (1), Holmes, et al. (3, 7, 9, 10) Brown and Birley (2) Clayton, et al. (4) Morrison, et al. (11) Murphy, et al. (12, 13) and Hudgens, et al. (8). These authors differed regarding the specific question of whether illnesses may be caused by emotion-producing stress. The first six of the above papers presented positive evidence for such a cause-effect relationship. The last four papers reported that psychiatric patients had significantly more interpersonal conflicts than did well persons or medically ill persons, at least while their psychiatric illnesses were in progress; but the latter authors were unable to find evidence that any type of stress, interpersonal or otherwise, played a causative role in the illnesses. Disagreements among all these workers may be traced to differences in both theoretical approach and methodology.