Four prepubertal children, all members of melanoma-prone families, developed pigmented scalp lesions that were diagnosed as dysplastic nevi. In three cases, the scalp lesions were the only evidence that the children were affected by the dysplastic nevus syndrome, a distinctive clinicopathologic entity that identifies persons at increased risk of malignant melanoma. In general, the skin of family members with dysplastic nevus syndrome does not show characteristic lesions until just prior to or with the onset of puberty. The presence of dysplastic nevi on the scalp may permit identification of at least some high-risk family members well prior to puberty. This should facilitate the early implementation of a melanoma prevention program for susceptible individuals and help ensure that melanomas are diagnosed early in their natural history, at a time when they are surgically curable.