I think the book is not only the best book on number theory, but the best textbook I have ever seen. Beginning students can gain a solid foundation in number theory, advanced students can challenge themselves with the often deep and always delightful exercises, and everyone, including experts in the field, can discover new topics or attain a better understanding of familiar ones. As with masterpieces in music in literature, one gets more out of it with each additional visit." - Béla Bajnok, Gettysburg College, The American Mathematical Monthly