The second edition includes many new topics and features:

. New sections in graph theory on distance, Eulerian trails, and Hamiltonian paths.

. New material on partitions, multinomial coefficients, and the pigeonhole principle.

. Expanded coverage of Pólya Theory to include de Bruijn's method for counting arrangements when a second symmetry group acts on the set of allowed colors.

. Topics in combinatorial geometry, including Erdos and Szekeres' development of Ramsey Theory in a problem about convex polygons determined by sets of points.

. Expanded coverage of stable marriage problems, and new sections on marriage problems for infinite sets, both countable and uncountable.

. Numerous new exercises throughout the book.

About the First Edition:

". . . this is what a textbook should be! The book is comprehensive without being overwhelming, the proofs are elegant, clear and short, and the examples are well picked."

- Ioana Mihaila, MAA Reviews