Sarah Cassidy

Sarah Cassidy


Sarah Cassidy

Dr Sarah Cassidy is an Educational, Child and Adolescent Psychologist and a peer-reviewed ACT Trainer. She is a Chartered Psychologist with the Psychological Society Of Ireland (PSI) as well as a serving Council Member of the PSI. She is also in the Division of Clinical Child and Adolescent Psychologists with the American Psychological Association.

She is the Founder and Director of Smithsfield Clinic, a private Community Mental Health Service in Athboy, County Meath where she has offered neuro-affirmative psycho-educational, neurodevelopmental, and emotional/behavioural assessments and treatment for all ages of children, adolescents, and young adults and their families for over 2 decades now.

She is also the Co-Founder and Co-Director of the New England Centre for OCD & Anxiety, Ireland Branch (with Dr Lisa Coyne) which is a highly specialised assessment and treatment centre for those experiencing anxiety ranging from everyday anxiety to very severe and treatment-resistant anxiety and OCD. This service employs ACT (+ERP) and RFT principles in all interventions. Dr Cassidy is also the Co-Founder and Chief Education Officer at which is a behavioural educational technological research company that came directly out of her doctoral research at Maynooth University (with Professor Bryan Roche) which continues to conduct cutting-edge behaviour analytic research nationally and internationally to evaluate how children learn best and to maximise their learning potential using Relational Frame Theory interventions and which is now widely known as SMART (strengthening mental abilities with relational training). Dr Cassidy is the former Chairperson of the Association for Contextual Behavioural Science Membership Committee and continues to serve on this and many other committees and SIGS within this organization, including being a member of the Steering Group for the Neurodiversity-Affirming Research and Practice Special Interest Group.

She has been a Lecturer in Child, Educational and Counselling Psychology at Maynooth University as well as a mentor and trainer to professional psychologists and behaviour analysts, ACT therapists and specialist teachers on multiple university programs and professional courses in Ireland and abroad for the last 15 years+. She regularly is invited to be a peer reviewer and guest editor for scientific journal articles and books. She is a clinical consultant on several professional boards and companies at senior management level including Compassionate Behavior Analysis and Reach Children Services both offering neuroaffirmative and compassionate behaviour analytic assessment and therapies.

Dr Cassidy has also designed a children’s mental health program, called MAGPIES, which is now being used in clinics all over the world to support children in learning how to build emotional regulation skills, build self and other awareness skills, increase self-esteem and to learn to cope with anxiety. She continues to conduct research nationally and internationally on this programme to improve mental health outcomes for children.

She has recently co-authored Tired of Anxiety; A Kid’s Guide to Befriending Scary Thoughts and Living your Life Anyway (which has recently been featured on several radio shows and popular podcasts) and Tired of Teen Anxiety; A Young Person’s Guide to Discovering Your Best Life and Becoming your Best Self. There are 3 more books in this series on the way. Dr Cassidy is best known for her ability to break down scientific principles into bite-sized pieces such that they can be understood by broader audiences, including children, adolescents, and those outside of the scientific community. She is passionate about building bridges, neuroaffirmative practice, and equitable access to evidence-based science.

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Research collaborations, The delivery of trainings / workshops, Supervision, One-to-one therapy sessions
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Athboy, The Municipal District of Kells, County Meath, Leinster, Ireland

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