Lindsey Criswell and colleagues report an association between three independent variants near TNFAIP3 and systemic lupus erythematosus (SLE). In a related study, Patrick Gaffney and colleagues report results of a genome-wide association study for SLE, also identifying variants in the TNFAIP3 region on 6q23 that are strongly associated with the disease. The same region on 6q23 has recently been associated with rheumatoid arthritis, but only a subset of risk alleles in this region seem to be common to both diseases. The TNFAIP3 (tumor necrosis factor alpha–induced protein 3) gene encodes a ubiquitin editing enzyme, A20, that restricts NF-κB–dependent signaling and prevents inflammation. We show that three independent SNPs in the TNFAIP3 region (rs13192841, rs2230926 and rs6922466) are associated with systemic lupus erythematosus (SLE) among individuals of European ancestry. These findings provide critical links between A20 and the etiology of SLE.