Abstract Theory of Schwarz Methods -- Two-Level Overlapping Methods -- Substructuring Methods: Introduction -- Primal Iterative Substructuring Methods -- Neumann-Neumann and FETI Methods -- Spectral Element Methods -- Linear Elasticity -- Preconditioners for Saddle Point Problems -- Problems in H (div ; ?) and H (curl ; ?) -- Indefinite and Nonsymmetric Problems -- Elliptic Problems and Sobolev Spaces -- Galerkin Approximations -- Solution of Algebraic Linear Systems.