The road to therapist–patient sex is paved with progressive treatment boundary violations. Except when a patient is raped, the therapist who eventually sexually abuses a patient follows a remarkably predictable “natural history” of therapist sexual misconduct. 40 Treatment boundaries are established by the therapist to define and secure the professional relationship with the patient to promote a trusting working alliance. 5 The observance of treatment boundaries supports the integrity of the therapist–patient relationship. Boundary violations are the symptoms, not the cause, of the therapist's mismanagement of the professional relationship with the patient.