Autism spectrum disorders (ASD) are common neurodevelopmental disorders characterised by a triad of impairments in reciprocal social interactions, verbal and non-verbal communication deficits with repetitive and stereotyped behaviours. The disorder may adversely impact not just the affected child, but also his/her family members. Currently there is no effective means for prevention, no biomarkers for early diagnosis and no specific treatment approach or a drug that can "cure" the disorder. Interest in ASD has exploded in the past decade following the vast increase in the prevalence of ASD to 1:100-1:150 in the most recent reports. The dramatic increase in ASD cases has been accompanied by an increase in public and professional awareness and an abundance of new research and treatment strategies. Autism is probably not a single disorder, but rather reflects many different disorders with broad behavioural phenotypes causing atypical development.