The purpose of this study was to replicate McCord, Thomson, & Iwata (2001) by developing and conducting an assessment and intervention for transition-related problem behavior, common in children with autism (Davis, 1987). Following some pre-assessment analyses, a functional analysis of problem behavior was conducted during transitions between activities; results suggested that problem behavior occurred in transitions involving a worsening in activity preference, for example terminating a preferred or neutral activity and initiating a non-preferred activity. Then, an intervention consisting of differential reinforcement of alternative behavior without extinction was implemented during the transitions identified as problematic; results suggested that problem behavior was effectively decreased in all targeted activity transitions. These data were presented at APBA 2015, ABAI 2015, BABAT 2015, APBA 2016, & ABAI 2016.