This chapter is a comprehensive reference manual providing information on the Child and Adolescent Scale of Participation (CASP), which is a newly developed instrument that has excellent internal consistency and shows evidence of content validity. The children and young people were aged from 4 months to 21 years, and time postonset ranged from 4 months to 6.5 years. Scores on the children and adolescent’s archived discharge data on the Pediatric Evaluation of Disability Inventory were compared with CASP scores. The CASP contains 20 items arranged in four domains: Home participation, Neighbourhood/ community participation, School participation and Home and community living activities. A brief history of the instrument's development is provided, along with a description of item content and administration/scoring procedures. Psychometric properties are reviewed and a critical commentary is provided. Key references are cited and in most cases the actual scale is included, giving the reader easy access to the instrument.