This book provides a comprehensive text on the geotechnical and geological aspects of the investigations for and the design and construction of new dams and the review and assessment of existing dams. The book provides dam engineers and geologists with a practical approach, and gives university students an insight into the subject of dam engineering. All phases of investigation, design and construction are covered, through to the preliminary and detailed design phases and ultimately the construction phase. This revised and expanded 2nd edition includes a lengthy new chapter on the assessment of the likelihood of failure of dams by internal erosion and piping.