This book encapsulates the analysis and design of buried gravity flow conduits, including pipe materials and soil materials and their interaction. These range from traditional pipes to open bottom concrete and corrugated metal culverts with spans of up to 25 metres, and include culverts, storm drains, sewers, and buried bridges. It begins with historical background and easily understandable design models then considers the properties of pipe materials and of pipe rings and backfill soils and the commonalities in their behavior. Finally, design methods consider the interaction of pipe and soil, along with simplified and computer methods. Much of this has been adopted by the AASHTO Committee on Bridges (responsible for highway culvert design) and other standards. The book will be important to any practicing engineer working on buried pipe design, including public engineers at all levels, private consultants, and product manufacturers, and will also suit researchers as a unified and comprehensive presentation.