Preface to First Edition Preface to Third Edition List of Symbols Chapter 1 Sphere Packings and Kissing Numbers Chapter 2 Coverings,Lattices and Quantizers Chapter 3 Codes,Designs and Groups Chapter 4 Certain Important Lattices and Their Properties Chapter 5 Sphere Packing and Error-Correcting Codes Chapter 6 Laminated Lattices Chapter 7 Further Connections Betwwen Codes and Lattices Chapter 8 Algebraic Constructions for Lattices Chapter 9 Bounds for Codes and Sphere Packings Chapter 10 Three Lectures on Exceptional Groups Chapter 11 The Golay Codes and the Mathieu Groups Chapter 12 A Characterization of the Leech Lattice Chapter 13 Bounds on Kissing Numbers Chapter 14 Uniqueness of Certain Spherical Codes Chapter 15 On the Classification of Integral Quadratic Forms Chapter 16 Enumeration of Unimodular Lattices Chapter 17 The 24-Dimensional Odd Unimodular Lattices Chapter 18 Even Unimodular 24-Dimensional Lattices Chapter 19 Enumeration of Extremal Self-Dual Lattices Chapter 20 Finding the Closest Lattice Point Chapter 21 Voronoi Cells of Lattices and Quantization Errors Chapter 22 A Bound for the Covering Radius of the Leech Lattice Chapter 23 The Covering Radius of the Leech Lattice Chapter 24 Twenty-Three Constructions for the Leech Lattice Chapter 25 The Cellular Structure of the Leech Lattice Chapter 26 Lorentzian Forms for the Leech Lattice Chapter 27 The Automorphism Group of the 26-Dimensional Even Unimodular Lorentzian Lattice Chapter 28 Leech Roots and Vinberg Groups Chapter 29 The Monster Group and its 196884-Dimensional Space Chapter 30 A Monster Lie Algebra? Bibliography Supplementary Bibliography Index