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Roy Thewissen Author

Lieve Bruyninx is the owner of Factor Psy, a mental health care training institute. She's a psychologist and peer reviewed ACT trainer with 20 years of behavior therapy expertise.

Yvonne Barnes-Holmes is the Co-Founder of Perspectives Ireland and Co-Developer of Process-Based Behaviour Therapy (PBBT). She has 25 years of experience in behaviour therapy.

Ciara McEnteggart is the Co-Founder of Perspectives Ireland and Co-Developer of Process-Based Behaviour Therapy (PBBT). She has 15 years of experience in behaviour therapy.

Marjolein Vleugel has been working as a Healthcare Psychologist for more than 20 years. She is the founder and head trainer of Expertise Centrum ACT.

Roy Thewissen, PhD, is a clinical psychologist and behavioral therapist. He works as a freelancer and at the pain department at Adelante rehabilitation clinic in the Netherlands.