Book excerpt: Considered a classic in the field, Troy Duster's Backdoor to Eugenics was a groundbreaking book that grappled with the social and political implications of the new genetic technologies. Completely updated and revised, this work will be welcomed back into print as we struggle to understand the pros and cons of prenatal detection of birth defects; gene therapies; growth hormones; and substitute genetic answers to problems linked with such groups as Jews, Scandanavians, Native American, Arabs and African Americans. Duster's book has never been more timely.