Preface; Part 1: Modelling fitness; Defining fitness in natural and domesticated populations, Stuart Barker; Genetic architecture of reproductive fitness and its consequences, Richard Frankham; Fitness traits in animal breeding programs, Mike Goddard; Discussion, John James; Part 2: Maintaining fitness; Maintaining genetic variation in fitness, William G. Hill and Xu-Sheng Zhang; Spherical cows grazing in flatland: constraints to selection and adaptation, Mark Blows and Bruce Walsh; Maintaining fitness by within breed selection, Piter Bijma; Discussion, Mike Goddard; Part 3: The genetic basis of adaptation; Some evolutionary consequences of niche construction, Kathleen Donohue; Genotype by environment interaction in farm animals, John James; Towards new ways of directly assessing fitness in Drosophila, Ary Hoffman; Discussion, Keith Hammond; Part 4: Strategies for managing diversity; Strategies to exploit genetic variation while maintaining diversity, Brian Kinghorn et al; Managing genetic diversity, fitness and adaptation of farm animal genetic resources, Louis Ollivier; Livestock genetic resources: preserving genetic adaptations for future use (summary), John Gibson; Discussion, Frank Nicholas; Concluding Summary; Stuart Barker's contributions to population genetics and animal breeding: exploring fitness, evolution and animal genetics, Frank Nicholas and Keith Hammond; Index.