Our team includes more than 300 professionals who are dedicated to enhancing the lives of the individuals we work with. We are all passionate about and relentless in our efforts to help our children progress.



Diana Campitelli, M.S.Ed., Executive Director- Waiver
Suzanne Heid, M.S., BCBA, LBA, Executive Director- Clinical and Education
Anne McHugh, M.A., BCBA, LBA, ABA Program Director
Tiffany Garner, Psy.D., Director of Psychological Services
Ryan High, BCBA, LBA


Kathy Niager, Ph.D., Founder


Diana Campitelli, M.S.Ed.

Executive Director- Waiver

Diana leads Trellis’ home and community-based Autism Waiver services. She is a graduate of the Johns Hopkins School of Education and holds a master’s degree and certification in special education. She gained experience in the classroom at the Kennedy Krieger Institute’s LEAP program and the High Road Academy of Howard County. She has been with Trellis since its inception in 2001 and has more than 15 years of professional experience educating children with autism.

“My compassion for children and families is why I do this work. A mother myself, I want to see kids at home with their families. What we do helps make that possible and that’s a rewarding feeling.”

Suzanne Heid, M.S., BCBA, LBA

Executive Director- Clinical and Education

Suzanne leads educational and clinical programming at Trellis. She holds a master’s degree in school counseling psychology from Western Maryland College and a bachelor’s degree in psychology from University of Maryland, Baltimore County (UMBC). Suzanne began her career at the Kennedy Krieger Institute and has over 15 years of professional experience designing and implementing highly successful treatment programs that meet the academic and behavioral needs of children with autism. Suzanne is a Board Certified Behavior Analyst and is also trained in the implementation of the ADOS, an assessment used in diagnosing children with autism.

Anne McHugh, M.A., BCBA, LBA

ABA Program Director

Anne McHugh is a licensed behavior analyst in the state of Maryland who has been working with individuals with autism spectrum disorders and other special needs in school, clinic and home settings since 1998. Prior to joining Trellis Services, she managed her own private practice in the Baltimore area for 8 years. Her practice was dedicated to providing Applied Behavior Analysis services to children while also providing consultation to families, other ABA companies, schools, and school systems. She also provided supervision to those pursuing BCBA certification. Anne earned a B.A. in Psychology from Loyola University, M.A. in clinical psychology from Towson University and Graduate Certificate in Applied Behavior Analysis from The University of North Texas. Anne is a member of the Association for Behavior Analysis International, the Association of Professional Behavior Analysts and the Maryland Association for Behavior Analysis.

“Children bring joy to my life each day. This fuels my passion to apply the science of behavior analysis to improve a child’s life”

Tiffany Garner, Psy.D.

Director of Psychological Services

Tiffany Garner is a licensed psychologist in the state of Maryland. She earned her Master’s and Doctoral Degrees in Clinical Psychology from Loyola University in Maryland. She completed her internship in pediatric psychology and post-doctoral fellowship in autism and feeding disorders at Mt. Washington Pediatric Hospital. Tiffany then served as medical faculty at MWPH where she developed the Assessment of Autism and Related Therapies Program. She specializes in the assessment and diagnosis of autism spectrum disorders as well as the treatment of anxiety, ADHD and behavioral problems. She is a member of the American Psychological Association, Maryland Psychological Association, National Register of Health Service Providers and Autism Society of America.

“One of the most rewarding aspects of my job is helping families understand their child by seeing the world through their child’s eyes. All that we do here helps make it possible for parents to reach their children and connect with them in new ways.”

Ryan High, BCBA, LBA

Ryan leads the clinical team at the Trellis Learning Center in Columbia. Ryan received his Bachelor’s Degree in psychology from Towson University, and his Master’s degree in Applied Behavior Analysis & Autism from The Sage Colleges. Ryan is a Board Certified Behavior Analyst and completed his clinical training while at the Kennedy Krieger Institute.

“My passion is providing treatment that enable individuals to navigate the world around them with happiness, confidence, and independence.”


Kathy Niager, Ph.D.


Kathy is the founder of Trellis and has been dedicated to serving children with autism in Maryland for the last 20 years. She received her master’s degree in community counseling from Georgia State University and her doctorate degree in school psychology with a minor in neuropsychology from the University of Georgia. During her two decades in the field of developmental disabilities, she has worked with children and their families through the Kennedy Krieger Institute and University of Maryland.

My passion is providing treatment that enables individuals to navigate the world around them with happiness, confidence, and independence.