This book is an absolute must have for those of us who love challenging mathematical problems. The book claims in its preface to be a continuation of Mathematical Contests 1997-1998: Olympiad Problems and Solutions from around the World, published by the American Mathematics Competitions. I made more than one attempt to find a copy of that book when preparing this review and was unsuccessful. (I have now been informed that the books from 1995-1996, 1996-1997, and 1997-1998 can be ordered from the American Mathematics Competitions web page.) We are fortunate that the Mathematical Association of America has decided to begin a new series of books, the MAA Problem Books Series, and has begun that series with this wonderful collection of problems from around the world.