Book excerpt: This book gives pharmaceutical scientists an up-to-date resource on protein aggregation and its consequences, and available methods to control or slow down the aggregation process. While significant progress has been made in the past decade, the current understanding of protein aggregation and its consequences is still immature. Prevention or even moderate inhibition of protein aggregation has been mostly experimental. The knowledge in this book can greatly help pharmaceutical scientists in the development of therapeutic proteins, and also instigate further scientific investigations in this area. This book fills such a need by providing an overview on the causes, consequences, characterization, and control of the aggregation of therapeutic proteins.