The author then discusses recent work on conditional reinforcement and on the discriminative control of behaviour and shows how operant research has changed our understanding of these important concepts in psychology. Subsequent chapters review research within the operant paradigm on the effects on behaviour of punishment, anxiety, aversive stimuli and drugs, again by emphasising the special contribution to these topics made by operant conditioning techniques and methodology. The final chapters consider the general implications of operant research for educational practice and for clinical psychology, and place this approach within the context of psychology as a whole. Dr Blackman argues that it should be recognized as one important attempt to further the scientific analysis of behaviour. This book, filled a long recognized need for an undergraduate text in this area at the time, and helped students form their own evaluation. Now it should be read in its historical context.