From the reviews: [...] an efficient reference book for many fundamental techniques of Riemannian geometry. [...] despite its length, the reader will have no difficulty in getting the feel of its contents and discovering excellent examples of all interaction of geometry with partial differential equeations, topology, and Lie groups. Above all, the book provides ... Read morea clear insight into the scope and diversity of problems posed by its title. S.M. Salamon in MathSciNet 1988 It seemed likely to anyone who read the previous book by the same author, namely Manifolds all of whose geodesic are closed, that the present book would be one of the most important ever published on Riemannian geometry. This prophecy is indeed fulfilled. T.J. Wilmore in Bulletin of the London Mathematical Society 1987 Einstein Manifolds is accordingly described as Besse's second book ... . there is no doubt that Einstein Manifolds is a magnificient work of mathematical scholarship. ... It is truly a seminal work on an incomparably fascinating and important subject. (Michael Berg, MathDL, March, 2008) The present book is intended to be a complete reference book. ... The book under review serves several purposes. It is an efficient reference for many fundamental techniques of Riemannian geometry as well as excellent examples of the interaction of geometry with partial differential equations, topology and Lie groups. Certainly the monograph provides a clear insight into the scope and diversity of problems posed by its title. (Adela-Gabriela Mihai, Zentralblatt MATH, Vol. 1147, 2008) Show Less