This article presents a conceptual model of altruism grounded in compassion in the health professions. The intent is to bring order out of the current conceptual chaos about the meaning and practical operation of these constructs. The theory-based model proposes that altruism is expressed as overt behavior in specific situations that vary in levels of intensity. It assumes that altruism is not a broad-based, cross-situational personal trait; that altruism can be measured objectively; and that altruism can be increased via education, practice and reinforcement. The article concludes by demonstrating the progression from formation of a theory-based conceptual model, development of objective measures, performing systematic research and accumulating an orderly and consensual body of knowledge about altruism grounded in compassion in the health professions.