Two children with autism who engaged in aggression and stereotypy were assessed using common analogue functional analysis procedures. Aggression was maintained by access to specific preferred items. Data on the rates of stereotypy and appropriate play were collected during an extended functional analysis tangible condition. These data reveal that once the child was given access to the items shown to be maintaining challenging behavior that these items were then used to engage in stereotypy. These results suggest a relationship between stereotypy and socially mediated challenging behavior. Potential modifications to standard functional analysis procedures designed to identify this relationship and the implications of this relationship for intervention design are discussed. (Contains 2 figures.)