This book presents design guidelines and hydraulic calculation methods of vacuum sewage systems in nine chapters. After a short history of vacuum sewerage, this book covers the theoretical basis of multiphase flows; a description of flows through collection pits, valves, and service laterals; empirical approaches for the dimensioning of vacuum pipes; and conceptual, mechanistic, and numerical two-phase flow models, including computational fluid dynamics modeling. In addition, methods for calculating forces on vacuum pipelines and principles of the design of vacuum pumping stations are presented. Furthermore, it summarizes design principles and calculation methods of two- and three-phase flows in both outdoor and indoor vacuum sewer systems and shows how the systems can be optimized, in particular by reducing their need for electrical energy. In addition to hydraulic methods, principles of structural design of vacuum lines are shown. Each chapter contains worked examples that illustrate the calculation procedures. This book is intended for designers, constructors, and operators of vacuum sewage systems and for students of fluid mechanics and environmental engineering. The last chapter lists the needs for further research, which may be useful for master's and doctoral students and their supervisors looking for topics for theses.