When applied to functional analysis results, structured visual inspection criteria have resulted in improvements in the levels of agreement between raters as well as earlier identification of the function of challenging behavior. However, multistep criteria can be difficult to apply in real time, which could be a barrier to widespread adoption in practice. This study evaluated a Microsoft-Excel-based functional analysis decision support system (FADSS), which could aid behavior analysts with interpreting functional analysis results. Final overall agreement between the FADSS and post hoc visual inspection was high at 95%. Final overall agreement between the post hoc results generated by FADSS and ongoing results generated by FADSS was acceptable at 81%, representing a 50% increase in efficiency. These results indicate that FADSS could aid behavior analysts when interpreting functional analysis results in real time.