Transition to school is particularly complex for children with special needs. A major difficulty faced by educational systems in trying to address these needs is the multitude of problems with which such children present. Based on population-level data collected with the Early Development Instrument in Canada, Australia, and Mexico, kindergarten-level school readiness outcomes in relation to particular impairments are explored here. Learning and behaviour problems have an overall impact on children's school readiness, while physical, hearing, and vision impairments appear to affect only the area directly related to the impairment. Overall, the results show some variation but also remarkable similarities among the countries. (Contains 6 tables.)