This chapter provides a framework for the issue of patient adherence to treatment in the context of the doctor-patient relationship and shows how communication between the doctor and the patient can have a profound impact. A consequence of the model of the doctor-patient relationship is that any problems with adherence are assumed to be due to the patient. The conceptualisation of adherence is important, as it underpins any attempt to address the problem of non-adherence. The problem of non-adherence has wider implications for the doctor-patient relationship than simply that the patient obtain the benefits of treatment. The consequence of defining both the doctor-patient relationship and adherence in this way is that the issue of non-adherence becomes a forbidden subject, which both parties are uncomfortable about discussing. Meichenbaum and Turk suggested the concept of adherence, rather than “compliance”, implies “a more active, voluntary collaborative involvemen in a mutually acceptable course of behaviour to produce a desired preventative or therapeutic result.”