The motivation for us to produce a treatise on regulation was mainly our convic- tion that it would be fun, and at the same time productive, to approach the subject in a way that differs from that of other treatises. We had ourselves written reviews for various volumes over the years, most of them bringing together all possible facts relevant to a particular operon, virus, or biosynthetic system. And we were not convinced of the value of such reviews for anyone but the expert in the field reviewed. We thought it might be more interesting and more instructive-for both author and reader-to...