Both the American Psychological and the American Psychiatric Associations have recently advocated specific courses in supervision for their trainees. Good supervision has been described in terms of specific competences or progressive skill sets, often measured via symptom reduction in the supervisee’s clients. Emphasis has also been put on adapting supervision, like treatment, to areas of diversity. But there has been less attention to general developmental goals such as the supervisee’s overall professional and personal growth, and to areas of maturation that constitute progress in both therapist and patient. This talk contextualizes clinical supervision historically, exploring some less frequently measured areas of supervisory competence. It aims to be relevant to the practical and professional needs of both supervisors and supervisees.