Dermatomyositis (DM) is a rare autoimmune disease defined by the presence of characteristic cutaneous findings, an increased cancer risk, and variable extracutaneous pathology involving the muscles, lungs, gastrointestinal tract, heart, and/or joints. Although the pathogenesis of DM remains incompletely understood, the discovery of myositis-specific autoantibodies has been an important step forward in understanding disease heterogeneity in DM and stratifying risk for extracutaneous disease and malignancy. Moreover, the recent elucidation of key immunologic drivers of DM has laid the groundwork for the development of novel, targeted treatments in the DM therapeutic pipeline.