When a species colonizes an area that it has not previously inhabited, it is called an "invasion", and it can result in the extinction of endemic species. The increase in numbers of humans travelling the world presents opportunities for invasions by organisms and the spread of diseases such as rabies and smallpox. Using the large amount of data from studies in pest control and epidemiology, it is possible to construct mathematical models that can predict which species will become invaders, which habitats are susceptible to invasion, and the biological impact. This book presents a clear and accessible introduction to the modeling of biological invasions. It demonstrates the latest theories and models, and includes data and examples from various case studies showing how these models can be applied to problems from deadly human diseases to the spread of weeds.