The purpose of this book is to introduce the phosphorus (P) removal structure as a new best management practice (BMP) for reducing dissolved P loading to surface waters from non-point source pollution. It provides guidance on designing site-specific P removal structures and instruction on the use of the design software, "Phrog" (Phosphorus Removal Online Guidance). The book initially reviews the nature and sources of non-point source P pollution, examines short and long-term solutions to the problem, and provides detailed theory on the design and operation of the P removal structure. As with many areas of study, one of the best methods of communicating concepts is through illustrations and examples. This book is no exception; several years of experience in studying P sorption and constructing P removal structures at multiple scales and settings are utilized to provide real examples and applications.