Petroleum engineers, drilling and production professionals, and advanced petroleum engineering students will welcome this important new book on annular flows in oil and gas well drilling operations. It is the only book on the subject presently available to the industry that combines rigorous theory, practical examples, and important applications. The book describes several annular borehole flow models that deal with eccentric, nonrotating flow, concentric rotating flow, and recirculating heterogeneous flow. These models are designed to handle the special problems that arise from drilling and producing deviated and horizontal wells, problems such as cutting transport, stuck pipe, cementing, and coiled tubing.