This one-stop reference is the first to present the complete picture -- covering all relevant organisms, from single cells to mammals, as well as all major disease areas, including neurological disorders, cancer and infectious diseases. Addressing the needs of the pharmaceutical industry, this unique handbook adopts a broad perspective on the use of animals in the early part of the drug development process, including regulatory rules and limitations, as well as numerous examples from real-life drug development projects. After a general introduction to the topic, the expert contributors from research-driven pharmaceutical companies discuss the basic considerations of using animal models, including ethical issues. The main part of the book systematically surveys the most important disease areas for current drug development, from cardiovascular to endocrine disorders, and from infectious to neurological diseases. For each area, the availability of animal models for target validation, hit finding and lead profiling is reviewed, backed by numerous examples of both successes and failures among the use of animal models. The whole is rounded off with a discussion of perspectives and challenges. Key knowledge for drug researchers in industry as well as academia.