Gil Boyne

Mark Thomas Gilboyne (October 28, 1924 – May 5, 2010), nom de guerre Gil Boyne, was an American pioneer in modern hypnotherapy.

In addition to his own practice, his main focus was on the training of "lay" hypnotherapists in Glendale, California; and, over some 55 years, he trained thousands of hypnotherapists globally with his Transforming Therapy methods. Many of his students wrote books and created their own hypnotherapy training centers.

Mentored by Ormond McGill — with whom he collaborated for Professional Stage Hypnotism (1977) — he championed the accessibility of hypnotherapy and consistently fought against legislative efforts worldwide to restrict hypnosis to the purely medical professions, which had largely ignored the therapeutic value of hypnosis until Boyne, Milton Erickson, and Dave Elman.