The terms are broadly interchangeable and may refer to the same practitioner. Generally, counsellor refers to a practitioner who is treating a client over a short period of time (for e.g. to treat negative behavior patterns). Therapist, on the other hand, can be used to refer to the same practitioner when she is treating a client over a long time period (for e.g. therapy sessions for deep-seated or complex psychological issues). Regardless of what the professional designation is, Counsellor Insurance is important to protect the practice.