This report describes a proband and his family consisting of 14 patients affected with simple congenital ptosis. Pedigree suggests an autosomal dominant pattern with 70-90% penetrance. The family includes patients with both unilateral and bilateral involvement, and cases with and/or without complex synkinesia. Left unilateral preponderance is striking, and pedigree analysis suggests the possibility of a modifier gene determining laterality. This study represents the first report of a large family with congenital autosomal dominant simple ptosis which demonstrates the full clinical spectrum of this condition.