Girls and women with autism are often undiagnosed, misdiagnosed or receive a diagnosis of autism at later age. This can result in adverse outcomes in their well-being, mental health, education, employment, and independence. The diagnosis of autism spectrum condition/disorder (hereinafter referred to as autism), with its current features linked with descriptions in the major diagnostic classification systems, is based primarily on observations and research on males. The term ‘Autism Spectrum Condition’ (ASC), used in this paper, has been coined by Simon Baron-Cohen and used in the professional literature for a decade to respect these individuals on the autism spectrum who feel that the term ‘disorder’is stigmatizing, whereas ASC presents both the strengths of these people and difficulties they experience. The research shows that autism in females has unique symptomatology and manifests itself differently, more subtly, especially in high-functioning girls and women, i.e., those with fluent speech, average or above-average intelligence quotient. The research also shows diagnostic stereotypes and lack of required sensitivity to identify autistic females. Additionally they do not reflect the unique presentation of autism in females demonstrated by greater compensatory capacity and an ability to develop sophisticated methods of ‘camouflaging’and masquerading. Furthermore, autism in females is associated with high comorbidity during adolescence including anxiety disorder, tic disorder, depression, high incidence of suicide, eating disorders, and high rates of other medical problems. Timely diagnosis, however, can reduce the difficulties that females with autism experience over their lifetime, allowing for the assessment of their needs regarding health, education, leisure, social relationships, and employment.