This article provides a conceptual framework for the study of explaining and uses that framework to review and discuss studies of explaining in various professional contexts including school and university teaching, medicine and medical consultations, nursing, other health professions and law. Explaining is a central activity in all these professions. Explaining may be described as an attempt to give understanding of a problem to another and understanding as seeing connections which were hitherto not seen. These definitions lead to a framework of problem identification, processes of explaining, checks on understanding and outcomes. The empirical studies indicate that clarity and expressiveness are highly valued and are key characteristics of effective explaining to groups, and that clarity and friendliness are key characteristics of explaining in consultations. Studies in various professions also show that training can lead to more effective explaining; that there are sometimes gaps between official wisdom and what professionals actually do and that ideologies and contexts influence problem identification, processes of explaining and outcomes.Explaining is a core skill of most professions. It is of obvious importance to teachers and lecturers but it is also of importance to lawyers, architects, engineers, medical practitioners and other health professions. Despite its ubiquity the study of explaining has been relatively neglected. There are perhaps three reasons for this neglect. First, some members of professional groups such as counsellors, therapists, social workers and teachers of adults associate explaining with authoritarianism. In so doing, they confuse authoritarianism and authority based upon expert knowledge and they assume that to explain is necessarily to be coercive. Secondly, explaining is a taken for granted activity. We all spend a great deal of time explaining in everyday life and in various professional contexts so we assume we know what an explanation is and how to explain. Thirdly, explaining, like many taken for granted