Juvenile idiopathic arthritis (JIA), the most common cause of chronic arthritis in children, is believed to be influenced by genetic factors. Recent studies on the genetics of JIA have not only validated proposed genetic associations but have also led to the recognition of novel genetic associations. Studies of specific genes have been modeled on the premise of shared autoimmunity, wherein genetic variants that predispose to other autoimmune phenotypes may also confer susceptibility to JIA. The advent of genome-wide association studies has accelerated the detection of non-HLA susceptibility loci in other autoimmune phenotypes and is likely to uncover novel JIA-associated variants as well. This review highlights recent genetic investigations of JIA.