Problem: Adherence to antidepressants is a major challenge in our health care system, with a high percentage of patients discontinuing their medications within six months. Aims: The purpose of this position paper is to discuss theoretical frameworks that address the psychological beliefs, benefits and barriers and feelings of autonomy that affect a person's willingness and motivation to take anti-depressant medications within a therapeutic relationship with a nurse practitioner. Methods: Three theoretical frameworks were selected to highlight particular perspectives relevant to enhancing patient motivation for medication adherence. The Self-Regulation Model, Health Belief Model, and Self-Determination Theory combined with motivational interviewing all offer guidance on strategies for improving adherence to antidepressants. Conclusions: The Self-Regulation Model underscores the importance of illness representations that prompt considering patient perceptions of depression that affect adherence. The Health Belief Model focuses on cost–benefit considerations that affect patient's adherence, along with perceived control. Finally, Self-Determination Theory combined with motivational interviewing offers strategies that enhance autonomy and optimize collaboration and motivation for adherence. Relevance for clinical practice: These three theoretical models are applied to a vignette for a patient who is having difficulty with adherence to antidepressant medication.