Generalized symmetric riemannian spaces.- Reductive spaces.- Differentiable s-manifolds.- Locally regular s-manifolds.- Operations with s-manifolds.- Distinguished s-structures on generalized symmetric spaces.- The classification of generalized symmetric Riemannian spaces in low dimensions.- The classification of generalized affine symmetric spaces in low dimensions.- Existence of generalized symmetric spaces of solvable type.- Irreducible generalized affine symmetric spaces.- Generalized pointwise symmetric spaces.- Non-parallel s-structures on symmetric spaces.- Some advanced results.