The new Psychodynamic Diagnostic Manual (PDM-2; Lingiardi & McWilliams, 2017) aspires to emphasize a holistic view of individuals, rather than focusing solely on the treatment of diagnoses or the amelioration of symptoms that constitute them. In this paper, we discuss the ways in which the PDM-2 differs from the Diagnostic and Statistical Manual of Mental Disorders, 5th ed. (DSM–5; American Psychiatric Association, 2013) and complements it as a tool. We discuss these topics in the context of studies within the field of psychotherapy research that seem to be relevant to PDM-2 syndromes and domains of functioning. We review some recent specific examples of psychotherapy research that help illustrate the role that different PDM-2 constructs play in treatment, as well as suggest ideas for future directions in research about the PDM-2. It is our hope that the PDM-2 diagnostic framework will aid in planning clinically sophisticated and methodologically robust research designs examining psychotherapy process and outcome.