PURPOSE OF REVIEW: Rheumatoid arthritis patients have higher risk for infections due to comorbidities, underlying immunosuppresion and use of glucocorticoids and disease modifying antirheumatic drugs. The association between treatment with antitumor necrosis factor alpha agents and serious infections, including opportunistic infections such as tuberculosis, in rheumatoid arthritis patients remains controversial. We present recent literature on this topic with a focus on clinical applications of this new data. RECENT FINDINGS: Prospective cohort studies and population-based registries have described the incidence and risk of serious infections in large rheumatoid arthritis patient populations of antitumor necrosis factor alpha users. Although some studies have suggested a one and one-half to two-fold increased risk, especially immediately after initiating the treatment, not all have shown an elevated risk for serious bacterial infections or tuberculosis. SUMMARY: Although antitumor necrosis factor alpha agents may be independent risk factors for infections there is an absolute low rate of infection in those treated with these agents (approximately 5 per 100 patient-years). Screening for latent tuberculosis with tuberculin skin testing is effective, and compliance with the recommendations for preventing this disease in recipients of antitumor necrosis factor alpha agents has partially decreased the risk of infections. Clinical suspicion toward developing infection in those being treated with antitumor necrosis factor alpha agents, particularly earlier in the treatment course, is important for effective management of patients. © 2008 Lippincott Williams & Wilkins, Inc.