Behavior Analysis is the scientific study of principles of learning and behavior. Two primary areas of study include the experimental analysis of behavior and applied behavior analysis. The experimental analysis of behavior is the basic science of the discipline and has, over many decades, accumulated a substantial and well-respected body of research literature on how behavior is learned and changes over time. The experimental analysis of behavior is the scientific foundation of applied behavior analysis (ABA). ABA is a systematic approach for influencing socially important behavior through the identification of reliably related environmental variables and the production of behavior change techniques that make use of those findings.

Practitioners of behavior analysis provide services consistent with the dimensions of ABA. Common services may include, but are not limited to, conducting behavioral assessments, analyzing data, writing and revising behavior-analytic treatment plans, training others to implement components of treatment plans, and overseeing the implementation of treatment plans. Behavior analysts are qualified to provide services to clients with a variety of needs, including improvements in organizational functioning (e.g., staff performance, management and pay structure interventions), skill deficits (e.g., communication, adaptive behavior), and problem behavior (e.g., aggression, self-injurious behavior), among others.

For the purposes of BACB certifications and examinations, the content of applied behavior analysis is contained in the BACB Fourth Edition Task List.