Moving into psychiatry, he worked with families at the Cassell Hospital therapeutic community.
Along with Camilla Bosanquet, Ben Churchill, John Heaton and Joe Redfearn in 1974, he helped to establish what later became the Guild of Psychotherapists.
[2] In 1980 he moved to Cambridge, where he helped to establish 'the Outfit' (later more formally known as the Cambridge Society for Psychotherapy), a non-hierarchical psychotherapeutic training organization based on students' collective learning and evaluation.
[1] Later that year the Cambridge Society for Psychotherapy organized a conference in his memory, 'The Legacy of Peter Lomas'.
[4] Papers from the conference were published in an issue of the European Journal of Psychotherapy and Counselling.