I am a non-stuttering SLP, but specialize in stuttering. I had a client who was very interested in hypnotherapy for stuttering, and there was a hypnotherapist in our area who claimed he could cure stuttering. My client wanted to try it out, but was apprehensive. I offered to go with him (I wanted to learn more myself), and the other therapist was very obliging. It was interesting. My client ended up ending the session halfway through because he was uncomfortable. The therapist clearly had a very structured method, which I respected. The client was awake the entire time, it was more like guided meditation. I had spoken with this therapist extensively ahead of time and can definitely say his knowledge of stuttering was very misguided, which was concerning from a treatment standpoint. His entire assumption was that all stuttering is caused by childhood trauma, so you can cure it by accessing the repressed trauma and working with that. The session was all about rooting around in old memories to try to find the trauma/first moment of stuttering. In one case I actually observed a false memory (client recalled watching a TV show that didn't exist at the time, but is popular now), because the therapist was pressing him to recall details. This was one therapist using one method, so that's all I can speak to. From talking to the therapist about good methods and theoretical premise, it makes sense that it would work for some people. It's essentially a hyper-targeted, intense dose of CBT paired with placebo effect mechanics (which are very effective!). I've met a few people who claim that hypnotherapy did cure their stutter, and I will never argue with someone's personal experience. Even though my background and bias is such that I don't recommend it to others, I think that if a person is open or curious about it, they may find value in exploring it.