An 11-year-old girl was followed up since birth because of hemihypertrophy of the left leg and thigh, multiple pigmented nevi and subcutaneous tumors typical of the Proteus syndrome. Because of clitoromegaly and scrotal-like hypertrophy of the labia majora, she had an endocrine evaluation the results of which were normal. The findings are thought to represent local genital hypertrophy. Ambiguous genitalia have to be added to the phenotype of the Proteus syndrome.