Numerous studies have used functional analyses to prescribe interventions for severe behavior disorders. The majority of these studies have focused on behavior that is dearly maintained by socially mediated reinforcement, such as contingent access to attention, tangibles, or escape from instructional demands. However, a significant proportion of functional analyses do not yield conclusive results. We examined interventions for 3 children with severe disabilities following incondusive functional analyses. First, preferred stimuli were identified for each child via a stimulus preference assessment. Second, a functional analysis was conducted for 2 of the 3 children. High rates of aberrant behavior were seen even (if not especially) in no-interaction sessions. The 3rd child was observed for several consecutive no-interaction sessions; behavior persisted in this condition. Third, interventions based on environmental enrichment were analyzed in an analogue setting. For all of the children, environmental enrichment decreased aberrant behavior if preferred stimuli were used in the procedure. To obtain further reductions in aberrant behavior, explicit reinforcement of toy play was required for 2 children, and a brief (5-s) time-out was necessary with 1 child. yses have proven to be successful, the generality of the current literature may be limited because most studies have focused on behavior that is clearly maintained by socially mediated reinforcement (e.g., attention, tangible reinforcement, or escape from instructions). In an epidemiological analysis, Iwata et al. (1994) reported that approximately 5% of their functional analyses of self-injurious behavior were incondusive, and more than 25% did not show a sensitivity to socially mediated reinforcement; Derby et al. (1992) reported that 34% of their clients displayed aberrant behavior that appeared to be maintained by automatic sensory consequences. Despite these data, disproportionately few studies have focused on the treatment of behavior disorders following undifferentiated results of functional analyses.The focus on interventions for behavior maintained by socially mediated reinforcement may be because an experimenter or clinician can control social contingencies. For example, if a behavior is maintained by attention, the environment can be arranged so that attention is withheld or delivered at the experimenter's discretion (e.g., Vollmer, Iwa-331 1994) 279 331-344 NUMBER2 (summER 1994)