For more than 10 years, the "Journal of Positive Behavior Interventions" has published, among other types of articles, behavioral intervention outcome studies related to positive behavior support. Operationally defining interventions is important to facilitating replication studies and adoption of intervention in applied settings. Furthermore, treatment integrity data are necessary to make valid claims that changes in outcomes resulted from intervention implementation and are thus essential to the internal validity of intervention outcome research. Reviews of treatment outcome research in related fields (e.g., applied behavior analysis) indicate that although many researchers operationally define interventions, a majority of researchers fail to report treatment integrity data. The purpose of this study was to review the treatment integrity data reported in all experimental intervention studies published in the "Journal of Positive Behavior Interventions" between 1999 and 2009. Results indicate that in recent years, a majority of published studies include a definition of the independent variable but do not provide quantitative treatment integrity data. (Contains 4 tables and 2 figures.)