Behavioural interventions for Autistic Spectrum Disorders (ASD) are among the most widely used approaches, and have proved both extremely popular with parents, and controversial with professionals. These behavioural techniques are some of the few practical applications of psychology in this area to be scientifically evaluated and validated, and this availability of evidence allows both their strengths and weaknesses to be debated. Much of this debate has focused on the initial claims made about these behavioural approaches two decades ago, and the scientific evidence following these initial claims often does not enter into the debate. However, there have been enormous developments and diversifications in the approaches offered by behavioural psychologists to the treatment of ASD, and this text now brings together new evidence regarding these contemporary developments in one place, offering an essential handbook of contemporary behavioural practice for ASD, provided by the key researchers in the field. This book provides detailed empirically-based reviews of many of the behavioural interventions that are used to help children and adults with ASD, and these chapters are organised into three sections for easy reference.