A Functional Behavior Assessment (FBA) is a process used to identify the purpose or function a challenging behavior serves for an individual. The four main functions typically identified are: escape, attention, access to tangibles, and automatic (sensory) reinforcement. By understanding why a behavior occurs, a behavior analyst can develop an effective intervention that addresses the root cause, rather than just suppressing symptoms. For example, if a child tantrums to escape a difficult task, the intervention might involve teaching a functional communication response (like asking for a break) and modifying the task demands. The FBA is a foundational tool in ABA, ensuring that interventions are ethical, effective, and individualized. It is not used to diagnose or to simply track frequency.