Overarching aim The aim is to clarify finer clinical differences, their aetiology and the long-term outcomes, within the subgroup of autism with IQ greater than 70. Specific Objectives 1. To investigate heterogeneity within a group of children with high-functioning autism by assessing within-group differences on language and communication abilities at the age of 2-3 years, 5-6 years and 8-10 years. 2. To assess longitudinal association between the three components of language: pragmatics, grammatical and syntactical; at three time periods: Time 1: 2-3 years; Time 2: 5-6 years; Time 3: 8-10 years