Book excerpt: This second edition of Genetics and Sports expands on topics previously discussed in an attempt to create an integrated and holistic understanding of the field of sports genomics. It is an update on technologies and on the role of genetics in training, performance, injury, and other exercise-related phenotypes. Ethical concerns and the importance of counselling before and after genetic testing are also addressed. It is increasingly important to understand the field of genetics and sports because of the potential to use and misuse information. All exercise scientists, sport and exercise clinicians, athletes, and coaches need to be adequately informed to ensure that genetic information is accurately and properly used. Genetics and Sports is, therefore, highly recommended to all of these groups.