The aim of this article is to show how the plan formulation method (PFM), an empirically validated method for case formulation based on control mastery theory (CMT), can help clinicians make sense of and use what they feel during sessions to better understand and treat their patients. We give a brief overview of the main psychoanalytic conceptions about countertransference, provide a brief introduction to CMT, and describe the concept of the plan and the PFM. We then show, using several brief clinical examples, how the components of the plan (patient’s goals, pathogenic beliefs, traumas, tests, and insights) may help understand clinicians’ in-session feelings.