Psychotherapy outcome research has shown that therapists vary broadly in the clinical results they produce. Part of this effect may be explained by individual variance in certain skills, abilities, and traits – such as emotional regulation skills and quality of adult attachment. Recent clinical research on the effects of psilocybin has shown evidence for rapid and large effects on personality, emotional functioning, and quality of life. Hence, the use of psilocybin in safe, controlled conditions might lead to changes in traits responsible for therapist effects. 50 psilocybin retreat attendees volunteered to participate in a longitudinal self-report survey to investigate effects on emotional regulation skills and self-rated attachment quality measured before the retreat and at two-weeks follow-up. Moderate-to-strong increases in emotional regulation skills were observed together with small-to-moderate decreases in attachment-related anxiety and avoidance. To explore how psilocybin may affect therapists from their own point of view, experiences of seven intensive short-term dynamic psychotherapy practitioners during and after a psilocybin retreat were gathered as brief essays that were thematically analysed. Their experiences provide some insight in how the potentially therapeutic effects of psilocybin are viewed through the eyes of therapists working in another modality, as well as how their own work could be affected in practice.