In this classic, originally published 25 years ago and now reprinted with a new Afterword by the author on how he came to write the book, Judson tells the story of the birth and early development of molecular biology, in the US, the UK and France. In particular, the fascinating account of the remarkable golden period from the revelation of the double helix structure of DNA through to cracking the genetic code and solving the basic problems of how genes are regulated, is told largely in the words of the main players in the unfolding drama, all of whom were interviewed extensively by Judson in preparing this acclaimed volume. As well as the new Afterword that appears here for the first time, the current edition contains the material added by the author to the earlier ''Expanded Edition'' (CSHL Press 1996) on some of the principal figures involved, particularly Rosalind Franklin, together with the Afterword added at that time which sketches the further development of molecular biology into the era of recombinant DNA.