About Us

Achieve with Autism Consultancy Ltd was formed in June 2016 to provide effective  Behavioural Intervention Services to children and young people with autism spectrum disorder and other related conditions. The company is based in South West London serving clients in London and surrounding areas.

Our approach to teaching and learning is person-centered and grounded in the foundation of the evidence-based practice of Applied Behaviour Analysis (ABA). We also work collaboratively with Speech and Language Therapists and Occupational Therapists.

We are fully committed to offering professional and high-quality services, whilst providing personal attention to our client’s needs.

We are dedicated to using the best evidence based Early and Intensive Behavioral Intervention and providing an outstanding personalised and comprehensive curriculum to improve the lives and outcomes for the children and young people under our care.

Esther Thomas holds an MSc in Applied Behaviour Analysis (ABA) – with a distinction from Bangor University, Wales (United Kingdom) and is a Board Certified Behaviour Analyst (BCBA). Esther has been working in the field of autism education and ABA for over 20 years.

She worked as a Senior Behaviour Analyst at TreeHouse School (Specialist School for children with autism and challenging behaviour) for 6 years. As part of the leadership team, she contributed positively though the principles of behaviour and multidisciplinary working and person-centred approach to enable pupils to achieve positive outcomes and develop essential skills and confidence needed for adult life.

Esther has extensive experience in providing consultancy for children and young people with autism across different settings. These include experience in designing and programming personalised and comprehensive curriculum, implementing and supervising, monitoring and evaluating ABA provision for children and young adults with autism.

Esther Thomas, MSc, BCBA

Esther Thomas, MSc, BCBA

Director, Consultant Behaviour Analyst

Esther has written and delivered high quality internal and external training on a variety of topics (i.e., Autism, ABA, Positive Behaviour Support, social and play skills, child development, challenging behaviours) to a range of audiences across different settings. She has designed and developed training programmes, models and assessments.

Esther has also successfully conducted training workshops and provided consultancy nationally and internationally (i.e. Brussels, Lebanon, Romania and Slovenia) resulting in positive outcomes of learners. 

Esther also worked as a Senior Behaviour Analyst – Training and Consultancy at Ambitious about Autism for 2 years. She was involved in developing a pilot early year’s assessment service and supporting pupils receiving pupil premium funding to achieve further academic attainment and progress. Esther also has experience in conducting pupil assessments, supporting with transitions, EHCP and assisting in writing tribunal reports and providing oral evidence at educational tribunals.

Esther Thomas is currently the Director and Senior Behaviour Analysts at Achieve with Autism Consultancy Ltd in London for the past three years. Achieve with Autism Consultancy Ltd provides personalised comprehensive home-based and school-based ABA (Applied Behaviour Analysis) programmes to enable learners (ages 2 to 19 years old) with autism spectrum disorder, developmental difficulties or related disorders to make progress and met their full potentials. 


"We spent many months searching for the right consultant. Esther came highly recommended from another parent, and as soon as we met her we could see why. She really took the time to get to know us as a family. Esther has taken a very holistic approach to our ABA programme to ensure we target all areas of our sons development, especially around communication, self help, independent play and academic skills. Since working with Esther, he has made incredible progress and we are confident that under her guidance, he will continue to achieve and reach his full potential."


"Esther Thomas is for me the best professional in the ABA field. She is supportive and helps me develop a good clinical practice in Slovenia at the Institute of Autism Spectrum Disorders. I would especially like to thank her for sharing her valuable expertise, research and for the encouragement and advice that she has provided. I would not hesitate to recommend her to anyone that wants someone who is efficient in the ABA field. "

Dr Ana Bezenšek

Special Education Teacher

"Esther Thomas is an amazing BCBA with so much experience in the field and dedication to her job. She inspires the whole team to work harder and makes sure that the child keeps progressing all the time. We are very lucky to have her on board as our consultant and I can wholeheartedly recommend her to anyone who is looking for the best ABA consultant for their kids"