Rheumatoid arthritis is a disease determined and influenced by many factors genetic, environmental, endocrine, psychological and immunological. Immunological mechanisms (hyperexpression of class II HLA antigens, cytokinin anomalies, functional deficiencies of certain lymphocyte categories, polyclonal activation of B lymphocytes with production of antibodies) suffice to maintain between them the immune response, synovial inflammation, and lesions of bone and cartilage. Progress in understanding these diverse pathogenic factors in RA will eventually lead more selectively targeted treatments to supercede the present empirical use of basic treatments.