There is a rapidly expanding field of research showing that ASD may manifest differently across the sexes, particularly among individuals with intact core language and intellectual abilities. Girls may have important socio-communicative strengths that “camouflage” their challenges and deficits related to ASD, which in turn places them at risk for under-diagnosis, delays in diagnosis, and reduced access to treatment. Although there is a growing sense among both researchers and self-advocates that autism may be camouflaged in girls, there is not yet a clearly established set of diagnostic differences by sex, necessitating further research in this area. The presentations in this panel will focus on differences by sex among autistic youth in performance on standard diagnostic tools used in research in and clinical practice for identifying ASD and co-occurring conditions, as well as associated disparities in access to care. Sex differences in both core domains of ASD and related areas of emotional-behavioral functioning will be explored. Data from the National Survey on Children’s Health will also examine disparities in psychotropic medication prescription rates as possibly related to differences in clinical conceptualization of co-occurring conditions.