Several theorists have speculated that schizophrenia constitutes a disorder in which there is minimal motivation to conform to social pressures, while manic-depressive psychoses represent disorders in which there is maximal motivation to conform to social pressures. However, there have been few experimental tests of these speculations, and those that have been conducted generally have yielded conflicting results because of methodological inconsistencies and limitations. The present investigation examined conformity behavior of male and female manic-depressives (MD), paranoid schizophrenics (PS), and normals (N) on two conformity tasks: attitude change and perceptual judgment. It was hypothesized that manic depressives would conform more than normals, who would conform more than paranoid schizophrenics (MD less than N less than PS). Results indicated that manic-depressives and normals conformed significantly more than paranoid schizophrenics, but did not differ from each other on either of the conformity tasks. Thus, the hypothesis was supported only partially. The results do not support the view that manic-depressive psychoses constitute disorders in which there is maximal motivation to conform to social pressures; however, the results do support the view that schizophrenia represents a disorder in which there is minimum motivation to conform. The results are discussed in terms of their implication for the uses of interpersonal psychotherapy forms.