This book provides an overview of recent developments in web theory. Webs (i.e. families of foliations in general position) appear in many different fields of mathematics (differential geometry, algebraic geometry, differential equations, symplectic geometry, etc.) and physics (mechanics, geometrical optics, etc.). After giving a survey on webs in differential geometry and algebraic geometry, the book presents new results on partial differential equations, integrable systems, holomorphic dynamics and nonlinear optics obtained through web theory. Contents: A Naïve Guide to Web Geometry (I Nakai); An Introduction to Web Geometry: Analytic Web Geometry (A Hénaut); Webs and Curvature (P T Nagy); Recent Developments: Conformal Flows on ∀ ,0 and Hexagonal 3-Webs (M Belliart et al.); Rigidity of Webs (J-P Dufour); Resonant Geometric Optics and Webs (J-L Joly et al.); Introduction to G -Structures via Three Examples (J M Landsberg); Web Geometry and the Equivalence Problem of the First Order Partial Differential Equations (I Nakai); Veronese Webs and Transversally Veronese Foliations (M-H Rigal); A Three-Dimensional Lagrangian Four-Web with No Abelian Relation (G F Robert). Readership: Researchers and graduate students in mathematics and physics.