This volume weighs in on the controversial subject of the roles genes play in determining aspects of physical and behavioural human variation. The author argues that genetic research is inadequate to support the conclusions that are often drawn in the media and technical journals about the genetic causes of such human traits as intelligence, depression, obesity, criminality and violence, and homosexuality. His concern lies in the ways that conclusions about the “genetic’ causes of certain human traits can be and do get used in legal, political and social decision making. The book makes the case that neither the information we have on genes nor on the environment is sufficient to explain the complex variations among humans.