Twenty-nail dystrophy may occur in adults as well as children. At the onset, the nails have longitudinal ridging and distal notching and splitting. With time they become thin and roughened. Clinically, the nail changes resemble those seen in lichen planus but other manifestations of lichen planus are usually absent. In children, the nail changes tend to involute spontaneously after a few years. Familial and congenital cases have been described. Twenty-nail dystrophy may be idiopathic or may be associated with alopecia areata, atopic dermatitis, lichen planus, or psoriasis. This 7-year-old boy has had nail dystrophy with near total nail destruction of all fingernails and some of the toenails since age of one year. His problem is idiopathic as he has no associated cutaneous disease and family history was negative for similar condition.