The interventions provided in the AIMSweb Behavior module were developed from the intervention science literature across disciplines of psychology and education. Each is designed to provide positive results immediately or in a brief amount of time. However, the actual amount of time in which positive results can be seen depends on the unique circumstances of each setting. Some straightforward interventions such as check in check out, self monitoring, or problem solving training should affect behavior immediately, but because schools are complex settings, more than one or two days worth of ratings is often needed to determine the effects of an intervention. When evaluating the effects of an intervention, always first check the “fidelity” of the intervention. Ask if each step was followed and if any feedback was provided to the person involved in the procedure. If this is established, and no evidence of change is seen (immediacy, trend or stability), three days is probably a sufficient trial. More likely however, is that some change will occur and may be small or variable. In such instances, it can be helpful to continue an intervention and have data for at least 9 days (or classes or recording periods). This “9x rule” gives you enough data to make decisions that are less likely to be chance. Exceptions to this rule of thumb should be made as needed, and always use common sense and professional judgment; for example, an intervention can be stopped or modified immediately if a student’s behavior becomes significantly worse, and an intervention should be stopped and a team assembled if a student’s behavior becomes threatening toward self, others, or property.