The selective cyclooxygenase 2 (COX-2) inhibitors have emerged as an important option in the treatment of rheumatoid arthritis (RA). Rofecoxib and celecoxib, the selective COX-2 inhibitors currently available, have shown efficacy in reducing symptoms of RA comparable with that of traditional nonsteroidal antiinflammatory drugs (NSAIDs). The primary advantage of selective COX-2 inhibitors relates to reduced gastrointestinal (GI) toxicity. Gastroduodenal ulcers detected by endoscopy are markedly diminished in patients receiving selective COX-2 inhibitors versus those receiving NSAIDs. Moreover, unpublished data indicate that the risk of symptomatic and complicated ulcers is reduced by approximately half in patients prescribed rofecoxib or celecoxib. Despite these encouraging findings, selective COX-2 inhibitors have the potential for important adverse events such as impaired renal function, hypertension, and edema. Furthermore, clinicians must balance the competing demands of reducing GI risk while managing the increasing costs associated with selective COX-2 inhibitor use.