André Weil’s mathematical work has deeply influenced the mathematics of the twentieth century. Part of a three-volume set, this work collects his papers in chronological order and includes lengthy commentaries on many of the articles written by Weil himself.

From the reviews "...All of Weil’s works except for books and lecture notes are compiled here, in strict chronological order for easy reference. But the value ... goes beyond the convenience of easy reference and accessibility. In the first place, these volumes contain several essays, letters, and addresses which were either published in obscure places (...) or not published at all. Even more valuable are the lengthy commentaries on many of the articles, written by Weil himself. These remarks serve as a guide, helping the reader place the papers in their proper context. Moreover, we have the rare opportunity of seeing a great mathematician in his later life reflecting on the development of his ideas and those of his contemporaries at various stages of his career. The sheer number of mathematical papers of fundamental significance would earn Weil’s Collected Papers a place in the library of a mathematician with an interest in number theory, algebraic geometry, representations theory, or related areas. The additional import of the mathematical history and culture in these volumes makes them even more essential." Neal Koblitz in Mathematical Reviews "...André Weil’s mathematical work has deeply influenced the mathematics of the twentieth century and the monumental (...) "Collected papers" emphasize this influence." O. Fomenko in Zentralblatt der Mathematik

certain rational varieties (spaces of straight lines, of conics, etc. ), whereas we shall emphasize the geometry on an arbitrary variety, or at least on a variety without multiple points. The theory of intersection-multiplicities, however, occupies such a centrat position among the topics which constitute the founda tions of algebraic geometry, that a complete treatment of it necessarily supplies the tools by which many other such topics can be dealt with. In deciding be tween alternative methods of proof for the theorems in this book, consistency, and the possibility of applying these methods to further problems, have been the main considerations; for instance, one will find here all that is needed for the proof of Bertini's theorems, for a detailed ideal-theoretic study (by geometric means) of the quotient-ring of a simple point, for the elementary part of the theory of linear series, and for a rigorous definition of the various concepts of equivalence. In consequence, the author has deliberately avoided a few short cuts; this is not to say that there may not be many more which he did not notice, and which our readers, it is hoped, may yet discover. Our method of exposition will be dogmatic and unhistorical throughout, formal proofs, without references, being given at every step.