The science / faith debate rages on. Richard Dawkins and others yield to the temptation to imply that their opponents are men of straw. Yet many leading scientists have an active Christian faith. Here 18 scientists, all esteemed by their peers, tackle two questions: What difference their faith makes to their scientific practice; and what difference their science makes to their understanding of their faith. Each was free to describe their personal experiences, the ways they have dealt with problems, or to reflect on their life as Christians in a scientific world. Many of the writers describe how they had to face up to reinterpreting their understanding of God or the Bible; crucially, none of them have had to compromise their beliefs because of their science.