This paper formulates a new conceptual framework for understanding profes sional culture in organizational context. Our analysis begins with an attempt to identify the complex interplay between individual sense-making, group beliefs and culture. The process of professionalization and the development of profes sional cultures is described and the influence of professional belief systems on organizational culture is examined. The inter-relationship between four different types of professional subculture and organizational culture is illustrated in a case- study analysis of an Australian home-care service. The stability of an organiza tion's operating environment is identified as a major factor which facilitates and constrains the propensity for professional subcultures to radically transform or incrementally refine dominant organizational cultures. The paper concludes with a critical reappraisal of the significance of professional subculture as a determin ant of an organization's cultural system.