This article proposes that the undifferentiated selfobject is the key to understanding the formation and treatment of disorders that are characterized by preoccupations with destructive thoughts and actions. The undifferentiated selfobject is a fundamental self-sustaining experience of knowing that there are ongoing and unknown happenings to be discovered throughout life that will be surprising, challenging, and self-sustaining. It is an extension of Heinz Kohut’s contributions of selfobjects that are necessary to the development of the self. Commonly accepted knowledge that there have been traumatic events in the early life of disordered patients points to disruptions of the development of the undifferentiated selfobject. These disruptions lead to preoccupations that are considered disorders. A treatment example of an obsessive personality disorder clarifies how understanding the undifferentiated selfobject was critical in delinking the patient from his preoccupation and allowing him to perceive and implement new directions in his life.