This chapter presents a case study on performance development with the case of a man who reported that he had been “ultra successful” in every facet of his business life and was happily married and living with his wife of three years in a large suburban home. He described himself as “feeling stuck”, which he described as the belief that he had gone as far as he could go without improving in fundamental areas in his life. The consequences of the avoidant behaviors led him to feel quite overwhelmed. Preintervention psychological functioning was assessed with a standard semi-structured interview and three self-report measures selected based on specific processes that appeared most likely to be relevant to the performer’s referral issue. The measures utilized included the Young Schema Questionnaire-Short Form, the Acceptance and Action Questionnaire-Revised, and the Profile of Mood States.