Robert Song considers some of the fundamental causal factors - attitudes and beliefs as well as scientific and commercial pressures - which have governed developments in human genetics, discussing them in relation to central ethical questions raised by Christian theology. Behind the development of technologies like genetic screening, cloning and `designer babies', he argues, are dominant cultural aspirations to `perfection' and absolute choice. `In response to this there is a need for an alternative vision of society and the human good, one which is not driven by the hectoring necessities that generate the technological imperative.'