Early diagnosis of language disorders and autism is important, and early intervention for autism and some language disorders makes a difference. Developmental surveillance of children to detect these disorders should be a routine part of medical practice. The persistence and pervasiveness of communication and socialising deficits differentiate children with autism from those with specific developmental language disorders. Hearing and vision assessment is essential in any communication disorder. Interventions, targeted to identified areas of need, should encompass communication enhancement, behavioural therapy, educational modification, parent education and family support. Pharmacological interventions have an important but discrete role in autism, but there are no magic bullets. It is important to remember that the normal childhood illnesses occur in children with developmental disorders. Parents should be directed to reliable websites on the Internet, and given information and books to read as well as phone numbers of relevant services (eg, autism associations). There is a need for increased government financial support for early intervention programs.