Medical or health sciences librarianship is viewed as a system whose components are the professional school, the professional group, and the professional association. As an open system it imports energy from these components, or subsystems, and transforms this energy into professionally identifiable products. The subsystems, in influencing the character of the medical and health sciences library profession, are interdependent and interrelated. However, linkages between the subsystems are becoming defective due primarily to lack of communication, information, and feedback. Stronger and more vigorous interaction among the subsystems is needed.