There is now a considerable body of knowledge conceptualizing the roles that public relations practitioners enact. A key element in the enactment of those roles is the competencies, or behaviors of those who occupy them, however there are no systematic studies of these competencies. Occupational psychologists who conducted in-depth interviews with 17 'top' communicators in the UK, discovered 10 core competencies or behaviors specific to the senior communication practitioner role in publicly quoted companies, and 10 core competencies for those working in the public sector. These competencies are elucidated and compared and the implications discussed. Avenues for further research are also identified.