Written for researchers and students in statistics, ecology, demography, and the social sciences, this book covers many modern developments of capture-recapture and related methods. With an emphasis on ecology, it helps readers understand model formulation and applications, including the technicalities of model diagnostics and checking. A wide range of real examples demonstrates the complexities that arise when describing extensive modern data. The book contains 130 exercises that extend the text and offers data sets, computer programs, and more online.