During the past 18 months we have studied 36 biopsy specimens taken from 11 young men ranging in age from 21 to 36, each of whom had multiple, reddish to violaceous papules, some distinctly verrucoid or velvety on either or both the shaft and glans of the penis. The clinical diagnoses accompanying the biopsy specimens were lichen planus, psoriasis and condyloma acuminatum. In no instance was carcinomia in situ suggested in the differential diagnosis. Histologically, however, all specimens submitted showed indubitable changes of squamous cell carcinoma in situ.