Depending on your needs and what you are looking to accomplish depends on the length of your session.
If you are scheduling a myofascial release session I would recommend an hour due to the sensitivity of this work and the time it needs to release and unwind.
Auto insurance is an hour for the first session and half hours after that.
If you are a new client coming in for a bodywork you must schedule an hour. This includes an assessment and discussion of your symptoms and goals. The only time you do not need to schedule an hours upon your first appointment is for a zone session.