As human populations and the resources required to support societies continue to grow, an increasing number of plant and animal species around the world are facing extinction. Given limited time, space, and money, how do we decide which management actions will be most effective to avert extinctions? In this book, many of the world's leading conservation and population biologists evaluate what has become a key tool in estimating extinction risk and evaluating potential recovery strategies - population viability analysis, or PVA. PVA integrates data on the life history, demography, and genetics of a species with information on environmental variability, using computer models ranging from simple measures of population growth rate to complex spatial simulations, to predict whether a given population will remain viable (i.e., not go extinct) under various management options. A synthetic and objective overview of the latest theoretical and methodological advances, Population Viability Analysis will be crucial reading for conservationists, land managers, and policy makers.