Dear Editors,We provide a reply to a letter to the editors in relation to ''Comparison of Behavioral Intervention and SensoryIntegration Therapy in the Treatment of Challenging Behavior'' (Devlin et al. 2010).We conducted a study using a robust design (''alternating treatments design''; Barlow and Hayes 1979) to provide an analysis, without prejudice, comparing the outcomes of two distinct interventions for challenging behavior in children with autism diagnoses. Crucially, this design allows separate interventions to be administered concurrently, by randomizing the order of intervention, giving opportunity for both interventions to be administered under the different stimulus conditions, for an equal number of times, across each of the conditions of administration (see Kazdin 1982). This design allowed for a thorough scientific analysis of two prevalent interventions, both aiming to alter rates of challenging behavior observed in children with autism diagnoses.The letter expresses concern in relation to three specific areas. Firstly, it declares that we have misrepresented sensory integration therapy in the approach that was used in our study. Our colleagues state that the approach used was not at all in keeping with the principles and practices of sensory integration. However, from the description of the design of interventions in our paper it is clear that we, the authors, had no role in the design of the sensory integration intervention for any of the four participants. All sensory integration interventions were designed by an occupational therapist with extensive expertise and experience in SIT, who had completed comprehensive direct observations of each participant over a period of one month. The kernel of this research program was to assess two types of interventions that are provided in ''real world'' school settings on outcomes for challenging behaviors. The sensory integration assessment and interventions were provided by an expert in this field and the functional behavior assessment and interventions were designed and facilitated by behavior analysts. Effectively, what is presented in this study under the intervention of sensory integration is a reflection of practice ''on the ground'' by an expert in sensory integration assessment and therapy. It was our aim to assess the outcomes of such an intervention to alter the rates of challenging behavior, not to design the sensory integration protocol. We therefore, did not misrepresent the practices of sensory integration in anyway but merely assessed the outcomes of an intervention that was recommended for the four participants included in the study.Our colleagues set forth that there was a failure to provide systematic and standardized assessment of the participants' sensory processing challenges. However, during the one month observation periods, prior to the design of sensory integration programs for participants, the occupational therapist did provide detailed assessments including direct and indirect assessments of each participant's sensory profile. Th...