This is a book about contemporary developments in the scientific understanding of genetics, and the ways in which these are transforming possible relations between humans and the world around them. It aims to encourage readers to critically examine social issues that relate to genetic science and practice, and to consider the links between social theory and the research and practice of genetic science. The focus is mainly, though not exclusively, on human genetics, exploring those developments which are seen as most significant in terms of public perceptions, social impact, or public policy. It covers a wide range of current and potential applications of genetic science and is clearly and accessibly written, assuming no prior biological knowledge on the part of the reader. Instead, genetic knowledge is placed in its social context.