The Missing Chums is volume 4 in the original The Hardy Boys Mystery Stories published by Grosset & Dunlap. The book ranks 108th on Publishers Weekly's All-Time Bestselling Children's Book List for the United States, with 1,189,973 copies sold as of 2001. This book is one of the "Original 10", generally considered to be the best examples of the Hardy Boys, and Stratemeyer Syndicate, writing. The original version of this title is noted for being the first Hardy Boys book in which Aunt Gertrude makes an appearance.