The aim of this study is to describe the developmental, familial and educational characteristics of 91 children with a clinical diagnosis of autism spectrum disorders (ASDs), from one educational district of Athens, Greece. Records of the 91 children, aged 4-14 years old, were examined with respect to sex, age of diagnosis, type of ASDs, school placement, co-existing disorders, parental ages, type of conception, prematurity and birth order. The results indicated that the boy:girl ratio was 4.3:1 while the average age of diagnosis was 6 years which implies a delay in the early detection of ASDs. Children with typical autism constituted 80% of the sample, while the Asperger group constituted 20%. The majority of pupils were served in general education, and only a small percentage attended special schools. The preferable type of support was one-to-one support in the classroom (47%). Among the most common disorders that coexist with the ASDs was ADHD, epilepsy, dyslexia and learning difficulties. Interesting findings were obtained for the advanced parental age, birth order and the relationship of assisted conception and premature birth with the presence of autism. The present study offers some useful insights about the characteristics of ASDs in a Greek school-based sample.