The main focus of this book is on brown adipose tissue and its metabolic function. The book provides a timely update on the latest research and shows where the field is heading. Brown adipose tissue (BAT) dissipates energy and has received considerable attention in the last few years, having been re-discovered in adult humans in 2007/9. Moreover, BAT might offer a target for novel therapies to address obesity, a health condition that has reached pandemic dimensions.