Oppenheim's or DYT1 dystonia is a primary dystonia typically presenting in a limb at an early age and usually becoming generalised within 5 years. Over the last decade research into this debilitating disorder has progressed considerably, enabling the identification of a genetic lesion (a 3bp deletion in the DYT1 gene) now widely accepted as the cause of a majority of cases. This case report presents the first molecularly diagnosed pedigree of an Australian family with DYT1 dystonia, which presented as writer's cramp in the 15-year-old proband and two of his cousins.