Neonatal-onset multisystem inflammatory disease (NOMID) is a rare, childhood-onset disease that is characterized by chronic, systemic inflammation. The purpose of this report is to describe the effects of interleukin-1 (IL-1) blockade on the clinical symptoms of 2 patients with NOMID. At the time of this report, the patients had been treated with anakinra (Kineret), a recombinant human IL-1 receptor antagonist, for 1.5 and 2 years, respectively. Both patients demonstrated rapid improvement in clinical symptoms and laboratory markers of inflammation. The use of anakinra in these patients seemed to be effective, without any safety concerns. These observations suggest that IL-1 plays a critical role in the pathogenesis of this inflammatory disease, and that blockade with anakinra should be further studied as a treatment for patients with NOMID and related disorders.