This study identifies positive and negative factors associated with physician well being. We collected two sets of data from physicians at a university-based Department of Medicine in Western Canada. First, we conducted exploratory, in-depth interviews with 54 physicians to identify factors associated with their well being. Participants explained that certain aspects of their work are demanding and negatively related to their well being, whereas other 5 factors are more enabling and contribute positively. Second, we mailed a structured questionnaire including measures of the key factors identified in the physician interviews to all physicians in the same Department of Medicine. Multivariate analysis was used to assess the extent to which the factors identified in the interviews are significantly related to physicians' well being. The findings show the importance of co-worker support, both in terms of being directly related to physician well being as well as buffering the negative effects of work demands. We discuss several important implications for physicians and the organizations that employ them in understanding the factors related to physician well being. In addition, patient interactions appear to be both a key source of stress and a major source of satisfaction in physicians' daily work lives.