Costa Mesa, California

Treatment is within your reach!

The Gateway Institute is pleased to expand its reach of specialized Obsessive-Compulsive Disorder (OCD) treatment to Orange County residents since 2008. Located in Costa Mesa, California. The Gateway Institute is committed to its long-term goal of offering accessible specialized treatment to those who suffer from OCD and anxiety-related conditions such as Post-Traumatic Stress (PTSD), Generalized Anxiety Disorder (GAD), Social Anxiety Disorder, Panic/Anxiety Attacks and Disorder, Body Dysmorphic Disorder (BDD), and Trichotillomania.

The treatment methods utilized at Gateway to treat anxiety conditions are cognitive-behavioral therapy (CBT), exposure and response prevention (ERP), exposure therapy (ET) and mindfulness-based behavioral therapy (MBBT).

Our Orange County, California, Gateway location is proud to provide OCD and anxiety treatment for the cities of Costa Mesa, Fountain Valley, Santa Ana, Garden Grove, Huntington Beach, Newport Beach, Laguna Beach, Fullerton, Irvine, Aliso Viejo, Cypress, Buena Park, Brea, Lake Forest, Tustin, Westminster, Orange and Anaheim.

Treatment Options

Meet Our Staff

The Gateway Institute
940 South Coast Dr. Suite 235
Costa Mesa, CA 92626
Office Phone: (714) 549-1030

Call to Schedule Assessment: (833) 432-5623

Hours of Operation:
Monday – Friday: 8AM-6PM

Meet Our Costa Mesa, California Staff

Jim Sterner

LMFT | Clinical Supervisor Lic. # 46088

Jim Sterner, LMFT, founder of The Gateway Institute, discovered his passion and interest in the treatment of Obsessive-Compulsive Disorder (OCD) while studying psychology at the University of Maryland and Antioch University. This passion and interest in the field of OCD drove him to further studies at Phillips Graduate Institute in … READ MORE

Chris Trondsen

LMFT | LIC. # 135118 | APCC Registration #6764

Chris Trondsen is a Licensed Marriage and Family Therapist (LMFT). He received his bachelor’s degree in human development and psychology from California State University, Long Beach. Additionally, Chris earned a Master’s of Science (M.S.) Degree in Counseling, … READ MORE

Ann-Margaret Mercier

AMFT | Registration#: 138078

Ann-Margaret Mercier, AMFT and APCC, completed her master’s degree in Clinical Psychology at Pepperdine University. At The Gateway Institute, she specializes in the treatment of obsessive-compulsive and related disorders (OCRDs) as well as anxiety disorders, utilizing evidence-based treatments such as exposure and response … READ MORE

Bahar Farzanmehr

ACSW | Registration #84051

Bahar Farzanmehr, MSW, is a graduate of Columbia University School of Social Work located in New York. She received her Master’s degree in Clinical Social Work, specializing in the mental health and well-being of individuals, groups, and families. From a young age, Bahar took an interest in psychology and decided… READ MORE

Jacques Esses

MSW | Registration# ASW96605

Jacques Esses is a registered Associate Clinical Social Worker. He earned his Master of Social Work (MSW) Degree, with an emphasis on individual and group clinical work at Yeshiva University, New York City. Jacques’ graduate thesis focused on the treatment of Obsessive-Compulsive Disorder (OCD) from an Exposure … READ MORE

Katharine Shiota

LCSW

Katharine Shiota is a licensed clinical social worker specializing in the treatment of obsessive-compulsive disorder (OCD) and related anxiety disorders. She earned her Master of Social Work from California State University… Katharine utilizes Cognitive Behavioral Therapy (CBT) as the foundation… READ MORE

Anna Liljenwall

Client Relations

Anna Liljenwall is the Client Relations Manager at The Gateway Institute and has been with the company since November 2023. She has been working in the mental health field since 2012 and earned her Bachelor’s Degree in Psychology from Southern New Hampshire University. Additionally, she is pursuing her Master’s Degree in Social Work… READ MORE