This paper presents an overview of the functions of connective tissue and the mechanisms of joint injury and contracture formation in relation to therapeutic exercise. The components of connective tissue operation are explained, including fibroblasts, macrophages, plasma cells, and collagen. An examination of the histology of connective tissue as it relates to joint motion limitations takes into account the importance of collagen synthesis. Three phases of the tissue repair process as they affect the joint capsule are summarized, and the factors that contribute to the degree of contracture, such as trauma and inflammation, are identified. Another aspect of contracture formation is introduced, involving myofibroblasts, an active process which decreases tissue flexibility. Experimental work in myofibroblastic contractures is now of interest in plastic surgery and hand surgery research. (FG)