Connective tissue disease is any disease that affects connective tissues of the body. Connective tissue binds together supports and protects organs. It is composed of two major structural protein molecules, namely collagen and elastin. Collagen consists of proteins clustered in bundles to increase the strength. Osteoarthritis is a painful, degenerative non-inflammatory joint disease that often involves the hips, knees, neck, lower back or small joints of the hands. Rheumatoid arthritis is a chronic inflammatory multisystem disease of unknown cause, characterized by progressive, destructive, symmetric inflammation and deformity involving the small joints of the hand, fingers, large joints, soft tissue and always associated with constitutional symptoms. The chapter also covers cervical spondylosis, ankylosing spondylitis, polymyositis, fibromyalgia, scleroderma, gout, and systemic lupus erythematosus.