Understanding invasion biology, and the dynamics of biological control practices, requires a multidisciplinary approach, embracing and integrating all the research tools at our disposal, particularly modern molecular and modelling techniques. This book provides a comprehensive and current overview of invasive alien arthropod predators and parasitoids through 20 chapters, contributed by 69 internationally renowned scientists (previously published as peer-reviewed papers in BioControl - August 2011), ranging from broad reviews of key topics on invasive alien species (IAS) to taxon-specific chapters. The context of invasion biology is given through nine chapters focusing on current themes but highlighting future directions and knowledge gaps. Concepts are explored in detail through ten chapters focusing on a taxonomically diverse range of arthropods. The concluding chapter presents an objective approach to considering the benefits and risks of exotic biological control agents.