As mentioned in the Preface, the book is a sequel to two earlier MAA publications of past IMO competitions; it is therefore similar in form to those books. The Problems section comes first, containing the statements of all 84 problems, in basically the same wording in which they were posed at the IMOs. The numbering is by the IMO year and, within each particular IMO, by a number from 1 to 6; the book begins with problem 1986/1 (the first question at the 1986 IMO) and ends with problem 1999/6.

In the Solutions section the problem statements are not repeated. The proposed solutions are rather detailed, especially the first solutions of problems to which two or more solutions are given. Some displayed formulas are numbered for the sake of further reference; their numbering starts anew with each subsequent problem (but it continues through the second and third solution to the same problem).

In the Results section the reader will find tables that, traditionally, present a summary of prizes and medals and the joint scores of contestants from participating countries. It must be, however, remembered that the IMO is an individual competition and that any countries ranking has an unofficial character.

The List of Symbols and Glossary come next. Terms and theorems that exceed the standard school syllabus, arranged in alphabetic order, are briefly explained. They involve no advanced mathematics, just some concepts and facts, used in this book, with which every student aiming at olympiads and contests should be acquainted. The explanations are meant as a reminder, and not a source for learning a theory.

The Subject Classification is an attempt to subject classification. This can be problematic, since problems that combine ideas from various fields of mathematics are very popular at IMOs. The reader may disagree with what is considered by the author as the “primary classification” of this or that problem.

Bibliography is the concluding section. There exists a vast literature on math contests, problem-solving techniques, and contest problem compilations elaborated by many authors from various countries; and most of these are excellent elaborations. Books that might be recommended are counted in the hundreds. Thus the bibliographical items included here are to be considered as a selection from a much broader offering—a proposal for possible further reading.