Dr. Paulo Pires, Ph.D., C.Psych.

Dr. Pires is a Co-Director of Halton Psychologists. He received his Ph.D. in School and Clinical Child Psychology from OISE/University of Toronto and is registered as a Clinical Child and School Psychologist with the College of Psychologists of Ontario. He is currently the Clinical Director of the Child and Youth Mental Health Program at McMaster Children's Hospital.  He is an Assistant Professor (Part-time) in the Department of Psychiatry and Behavioural Neurosciences at McMaster University, and current supervisor and former Training Director for the Clinical Child Psychology Residency at McMaster Children's Hospital.  He previously worked for the Toronto Catholic District School Board for several years. 

Dr. Pires is a founding partner of Halton Psychologists, a private practice in Milton.  He completes psychological assessments of children and adolescents and uses a Cognitive Behavioural, Interpersonal and Family Systems approach to the treatment of children, adolescents and families.  Dr. Pires teaches and supervises trainees in psychology and psychiatry at McMaster Children's Hospital.  He is also involved in disseminating knowledge through workshops and publication.


Dr. Olivia Ng, Ph.D., C.Psych.

Dr. Ng is a Psychologist at Halton Psychologists.  She holds a Ph.D. degree in psychology from OISE/University of Toronto.  Over the last 10 years, Dr. Ng has acquired specialized knowledge in clinical psychology through her work with children and adolescents.  She has provided psychological assessments and psychotherapy to help those experiencing mental health problems overcome their challenges in a variety of settings including the Centre for Addiction and Mental Health (CAMH), Surrey Place Centre, Toronto District School Board, University of Waterloo, and Mount Sinai Hospital.  Currently, Dr. Ng works at McMaster Children’s Hospital in the Autism Spectrum Disorder Program and Developmental Pediatrics and Rehabilitation Program.

At Halton Psychologists, Dr. Ng provides therapy to children and adolescents with mood/anxiety disorders, learning issues, and behavioural problems that incorporate the Family Systems and Cognitive-Behavioural Therapy approaches.  In addition, she conducts comprehensive psychological assessments.  Dr. Ng has published in peer-reviewed journals and presented at conferences.

Dr. Shonna John, Ph.D., C.Psych.

Dr. John is a Co-Director of Halton Psychologists and a Clinical Child/Adolescent Psychologist and School Psychologist.  She obtained her doctorate degree from the University of Toronto in 2005 and received dual registration from the College of Psychologists of Ontario in 2006. She has worked extensively in private, hospital, community and school settings throughout the years including Trillium Health Partners, Hospital for Sick Children, McMaster Children's Hospital, Integra Foundation, Surrey Place Centre, Toronto Catholic and Peel District School Boards.

Dr. John is a founding partner of Halton Psychologists, a private practice in Milton.  At Halton Psychologists, she focuses her work on children and adolescents who experience distress due to anxiety disorders, mood disorders, learning difficulties, ADHD and various behavioural concerns.  She assumes a Cognitive-Behavioural Therapy and Family Systems approach to helping children and families develop lifelong skills to manage their difficulties.  Dr. John has authored various publications and articles, which have focused on children's mental health.  In addition, she continues to train and supervise other mental health professionals and to engage in disseminating knowledge at various workshops.


Dr. Vicky Timmermanis,
Ph.D., C. Psych.

 Dr. Timmermanis is a Psychologist at Halton Psychologists. She received her doctoral degree in school and clinical psychology from OISE/University of Toronto.  She has experience working with children and youth in a range of settings including schools, children's mental health centres (ROCK) and hospitals (McMaster Children's Hospital, Toronto Western Hospital). In addition to her work at Halton Psychologists, Dr. Timmermanis also works part-time at the Toronto District School Board

At Halton Psychologists, Dr. Timmermanis conducts comprehensive psychological assessments of children and youth. Through these assessments, she aims to meet the goals of the family, to understand each child/teen's unique strengths and needs, and to provide recommendations to support their academic progress and emotional well-being.