This review examines the evidence for screening for autism spectrum disorders in the general population and the information needed to inform screening policy. The UK National Screening Committee criteria are taken as the framework. These criteria cover the condition, the screening test, the treatment and the screening programme as a whole. With respect to the condition, reasons for variation in prevalence estimates for autism spectrum disorders need to be resolved and there are few longitudinal studies to describe the natural history of autism spectrum disorders that include data on children identified at an early age. There is no screening test suitable for use in a population setting that has been fully validated. There is insufficient evidence regarding the effectiveness of interventions. This review supports the current policy position of the National Screening Committee, that on the basis of existing evidence, screening for autism spectrum disorders cannot be recommended. (Contains 3 tables and 1 figure.)