Abstract: Diagnosis is a socially and conceptually fraught feature of modern mental health treatment. This paper describes three conceptualizations of diagnosis: as clinically informative, socially constructed, and ethically relational. The paper represents each position with the perspective of clinicians, critical thinkers, and philosopher Emmanual Levinas, respectively. While they are not mutually exclusive, each having their own legitimacy and utility as well as problematic features, they do at times oppose each other, and holding each at once is a challenge for therapeutic work. The first two conceptualizations of diagnosis (clinical and constructionist) point clearly to avenues of conflict. However, the third force, while still providing potential for conflict, may also do much to moderate the tendency of both ends to exclude each other’s legitimacy, or perhaps even work between the two as a mediating factor. The three conceptualizations are then explored in a case vignette from my work in a community mental health center.