This chapter provides a comprehensive overview of rheumatoid arthritis, covering its clinical features, diagnostic criteria, relevant investigations, and management strategies. Typical articular manifestations include the insidious onset of symmetrical pain in small joints—sparing the distal interphalangeal (DIP) joints—with morning stiffness lasting over 30 minutes. A detailed table of extra-articular manifestations is also included. Key laboratory tests include C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), anti-citrullinated peptide antibodies (anti-CCP), and rheumatoid factor. Radiographic findings often reveal periarticular osteopenia, marginal erosions, and joint space narrowing. Initial pharmacological management includes NSAIDs and short-term low-dose corticosteroids. Referral to a rheumatologist is recommended for initiating disease-modifying antirheumatic drugs (DMARDs) or evaluating unexplained synovitis. Surgery may be considered in cases of severe joint deformity, persistent pain from structural damage, or complications such as nerve compression.