This is a big book dealing with molecular biology in considerable detail. It is organised in 24 chapters subdivided in small paragraphs each one dealing with a particular problem in molecular biology. The book covers the basics first and then deals with more specific matters like immunology, cancer, development, etc all seen from the molecular biologist point of view. Although the approach is purely mechanistic it uses a clear evolutionary orientation, well explained at the beginning of the book, that helps to give a dynamic framework to the whole subject. This is not a book to be read in only a few weeks but roughly a year's time, given the detail and amount of material exposed.