Statistics show a higher diagnosis of autism in boys than girls, with data in the UK showing a ratio of 4:1 (Ambitious About Autism, 2017). However, as available statistics are generally based on multiple studies, both national and international, this ratio is likely to be lower.  Recent research in the USA suggests a ratio of 3:1 (Loomes et al., 2017). Rachel Loomes and her colleagues, in their systematic review of male to female ratios in autism suggest that girls who meet the autistic spectrum disorder (ASD) criteria are at a greater risk than boys of not receiving a clinical diagnosis. Rivet (2011) on the other hand, suggests that boys may be more likely to show hyperactivity or aggression than girls, which would lead to a clinical examination. Other researchers suggest that autism may present differently in girls or girls may ‘camouflage’ symptoms (Dworzynski et al., 2012). What the research highlights is that autism in girls is probably more common than was previously thought and that girls on the autism spectrum may present with different or less pronounced symptoms or may mask the symptoms. In many situations it may not lead to a clinical diagnosis.