Rheumatoid arthritis is a chronic, progressive, inflammatory joint disease, affecting primarily the small joints of the hands and feet symmetrically and characterized by joint destruction, progressive disability, and premature death. Rheumatoid arthritis shows a wide spectrum of clinical phenotypes from mild disease to severe arthritis. Aggressive disease implies a rapidly progressive course affecting most joints, with little or no response to drug therapy, and sometimes complicated by life-threatening extraarticular involvement. The eventual multiple joint destruction requires major surgery, and severe disability results in loss of occupation and dependence on others. Many prospective cohort studies have attempted to predict outcomes and develop prognostic markers, especially in early disease. Probably most useful are those factors that independent of disease activity, such as the presence of rheumatoid factor, the so-called shared epitope of HLA-DR. In addition, clinical indicators (e.g., higher affected joint counts, the presence of extra-articular features, subcutaneous nodules, considerable degree of physical disability at onset), laboratory variables (e.g., longstanding increased acute-phase response, decreased hemoglobin) are indicating a poor prognosis. Some sociodemographic markers, such as female sex and a lower level of formal education are associated with a poor prognosis. An ideal prognostic marker should be reliable, simple, accurate and independent of the stage and inflammatory activity of RA so that they can be used early of the disease. Patients with a poor outcome should be treated promptly and aggressively with disease-modifying antirheumatic drugs to limit or prevent further disease progression.