This paper details a semi-automated method that can calculate intervention thresholds—that is, the minimum required intervention sizes, over a given time frame, that result in a desired change in a system’s output behavior pattern. The method exploits key differences in atomic behavior profiles that exist between classifiable pre- and post-intervention behavior patterns. An automated process of systematic adjustment of the intervention variable, while monitoring the key difference, identifies the intervention thresholds. The results in turn can be studied and presented in intervention thresholds graphs in combination with final runtime graphs. Overall, this method allows modelers to move beyond ad hoc experimentation and develop a better understanding of intervention dynamics. This article presents an application of the method to the well-known World 3 model, which helps demonstrate both the procedure and its benefits.