Psychotherapists in private practice are generally required to have a plan in place in the event they die or become incapacitated (often called a "professional will"). Unfortunately, many if not most psychotherapists and counselors do not have such a plan in place. Some do not know that such a requirement even exists. Others simply haven't gotten around to doing this, just like many others haven't gotten around to creating a foundational estate plan. And yet others simply do not know where to go to create such a plan, because services in this arena are sorely lacking and often inadequate or problematic.
The reasons for this requirement is fairly straightforward. If a therapist dies or becomes incapacitated, first and foremost, we do not want the therapist's patients to find out by coming to the therapist's office for an appointment and finding the therapist mysteriously missing for a period of time. We want a system in place so that patients will be notified and referred to an appropriate clinician as soon as it is realistically possible to do so. The other reason has to do with patients' right to their clinical files and to confidentiality. Under federal and state laws, clinical files must be kept in compliance with privacy standards and for a prescribed amount of time so that a patient or other appropriate person might have access to such files even after treatment has ended. These files must be handled by an appropriate clinician (and not the therapist's friend or spouse, unless that person happens to be an appropriate licensed clinician) who will safeguard patient confidentiality and destroy the files at the appropriate time.
If you are in therapy, you should ask your therapist if she/he has a professional will. Very few attorneys know about professional wills and the legal/ethical/practical issues involved in creating them. There are a few online solutions, but most of them are created by therapists. Just as you wouldn't necessarily go to a lawyer for your psychological counseling, you might not want to go to a therapist for a document that is most similar to a will. Therefore, the best solution would be either going to a knowledgable attorney or using an inexpensive Internet solution vetted by estate planning lawyers.
Below are some of the rules that apply to most California therapists.
Licensed Marriage and Family Therapists: California Association or Marriage and Family Therapists Code of Ethics Rule 1.3
Licensed Clinical Social Workers: National Association of Social Workers Code of Ethics Rule 1.15
Psychologists: American Psychological Association Code of Conduct Rules 3.12 and 10.09; also California Business and Professions Code section 2919*
Licensed Professional Clinical Counselors: American Counseling Association Code of Ethics Rule C.2.h.
Note that most of the above requirements are national. This means your therapist probably must follow the same requirements no matter what state the therapist is in.
*A bill has been introduced in the California Senate which will make the requirements of B&P Code section 2919 apply to all private practice psychotherapists.