Dual relationships vary and are commonplace in non-Western cultures and in many professions. In counseling, dual relationships may exist between a counselor and a client, a counselor and a counselor-in-training (CIT), or two counselors participating in peer supervision. To better understand dual relationships in counseling supervision, this paper seeks to define the topic, investigate it in terms of sexual and non-sexual relations, explicate available guidelines and best-practices, identify areas for future research, and pose reflections on dual relationships confronted through the author's experience with peer supervision.