Psychoanalysis:

“I never met Freud personally but I corresponded with him and he wrote to Jung expressing the hope that I would further the cause of psychoanalysis in Italy. But I soon became a heretic. With Jung, I had a more cordial relationship. We met many times during the years and had delightful talks. Of all modern psychotherapists, Jung is the closest in theory and practice to psychosynthesis.”

—Roberto Assagioli
(from an interview with Sam Keen, Psychology Today, December 1974, p. 2)