The document provides an overview of behaviourism in psychology. It discusses the key figures of Edward Thorndike, Ivan Pavlov, John Watson, and B.F. Skinner and their major contributions. Behaviourism rejected unobservable mental events and focused on observable stimuli and responses that could be scientifically studied. While behaviourism was highly influential for decades, its dominance has declined as other approaches in psychology emerged that considered additional factors beyond direct environmental influences.