Children with autism are able to show secure attachment behaviours to their parents/caregivers. Most studies on attachment in children with autism used a (modified) Strange Situation Procedure (SSP) to examine attachment security. An advantage of the Attachment Q-Sort (AQS) over the SSP is that it can be attuned to the secure-base behaviour of children from special populations. In this study experts in the field of autism (both clinicians and researchers: N = 59) defined an AQS criterion sort for children with autism and tested its content validity. Separate criterion sorts were defined for the social subtypes aloof and active-but-odd, but the two criterion sorts could be combined into one AQS criterion sort for children with autism. It is concluded that with minor amendments the original Attachment Q-Sort is applicable in observing the attachment behaviour of children with autism. (Contains 2 tables.)