Abstract This manual is a guide to the selection, installation, field testing, and maintenance of water distribution valves. Although the manual focuses on distribution valves, other valves, primarily used in plant operations, are also discussed. It provides guidance on generally available valve alternatives. Information contained in this manual is useful for operators, technicians, and engineers in a utility of any size, but it is particularly useful for small- and medium-sized organizations. The manual deals only with the more commonly used valves, including: globe, butterfly, plug, ball, cone, gate, and check. Special-use valves are also discussed, but the intent here is only to introduce their availability and applications. Chapter 1 includes a brief historical review of valves and major design considerations, such as flow resistance, flow control elements, and sealing mechanisms. Chapter 2 introduces the major types of valves and the parameters that need to be considered when selecting a valve. Chapter 3 discusses valve tests, unloading, inspection, and storage. Chapter 4 presents guidelines for valve installation. Chapter 5 discusses the operation and maintenance of valves including: planning a maintenance schedule, valve maintenance procedures, and record keeping.