AbstractForty male inmates from an adult correctional training centre participated in a 2 × 2 factorial design with subject correctness‐incorrectness and group agreement‐disagreement constituting the classification factors. A modified Asch procedure was used to manipulate a S's prior experience of correctness and agreement (Part 1) and to assess subsequent conformity to 3 male confederates (Part 2). The female experimenter served as the source of reinforcement and group correctness. Ss responded to a (two part) 26 verbal and perceptual item scale, including 11 conformity items.Subject correctness and group agreement interacted, for perceptual items only, so that subjects who were more competent than the group or equally incompetent to the group conformed less than those who were less competent than the group, who in turn conformed less than those who were equally competent to the group, where both the subjects and the group were correct. Subjects conformed more to difficult verbal items than to perceptual items, and unsuspicious subjects conformed more than suspicious subjects. Both relative competence, mediating the effects of prior experience, and the situational factor of reinforcement affect conformity to perceptual t