From what I understand, it depends on the surgeon and also the therapist. My therapist had a headquarters that is specific to trans related issues. After being in therapy for so long, the therapist recommended me to the headquarters. I then had to go in front of the committee to be approved and then the entire committee sent off letters to my surgeon. It was a bit of a pain of a process, but that way, the surgeon couldn't ask for more referrals since I already had 8 or so. Some surgeons only require one referral while some require two: one from a therapist and one from a medical doctor. Hope that helps!