Janet Sprent has produced a slim volume on legume nodulation with a global emphasis on the distribution of legumes, their biology, agronomic uses and microbial microsymbionts. The purpose of this book is not to be a comprehensive treatise on the huge family of legumes which has already been done in the excellent work of Lewis et al. (2005). Instead this book is worth its weight in gold because over and over again it points out the role of legumes in agriculture all over the world. It highlights species that have been unfairly neglected such as Bambara groundnut that is a popular food source in Africa. Overall, one of the greatest strengths of this book is that it gives a balanced summary of the biology of legumes and rhizobia that can be read by a wide audience. In the approaching age of climate uncertainty and food scarcity this is a timely book reminding us that legumes, and their bacterial mates, are one of mankind's greatest allies in sustainable agriculture.