Preface.- Introduction.- Finite Reflection Groups.- Coxeter Groups.- Coxeter Complexes.- Buildings as Chamber Complexes.- Buildings as W-Metric Spaces.- Buildings and Groups.- Root Groups and the Moufang Property.- Moufang Twin Buildings and RGD-Systems.- The Classification of Spherical Buildings.- Euclidean and Hyperbolic Reflection Groups.- Euclidean Buildings.- Buildings as Metric Spaces.- Applications to the Cohomology of Groups.- Other Applications.-...