Early and intensive behavioral intervention outcome research includes descriptions of intervention variables that may increase treatment success. This study was designed to develop an observation system that incorporates and expands on some of these variables. Measures include the number of interventionist teaching units, types of skills addressed during instruction, consequences programmed by interventionists, and engagement with teaching materials. This system allowed for a view of the differences in teaching behaviors among the participants. It is proposed that this observation system is a start toward standardized intervention measures that can be applied to evaluate varied treatment models. Such standardization can help in ensuring that all children have access to evidence-based services.