This is the first single-volume handbook with the information a researcher needs to select the best rheology modifiers for his/her project. Information on 20 different types of rheology modifiers manufactured by 26 companies worldwide is described. These range from Acrylic Polymers to Xanthan Gum. This handbook was written because, in the authors' experience, the selection of a rheology modifier for specific applications is an arduous task. It requires researching the technical literature of numerous suppliers, contacting them for current information and recommendations, and paring the list of candidates from hundreds to a few dozen. This book will enable readers to easily identify the best candidates for an application with a minimum investment of time.The book is divided into four sections. Part I reviews rheology fundamentals. Part II presents details on the products available from the 26 represented companies. Part III focuses on the selection of suitable rheology modifier candidates. Part IV is a formulary containing the contributions of the suppliers.