Where the Wild Things Are

US Harper & Row, 1963, is the true first (the UK Bodley Head edition followed years later). The single most reliable point is a first-issue jacket with NO Caldecott Medal seal. After the 1964 Caldecott award the publisher recalled the edition and re-jacketed it with a medal jacket (now only two blurb paragraphs on the front flap, and the award noted on the rear), so a first-printing book can be found in either jacket — the no-medal jacket is the true first issue. Sendak-signed firsts are especially desirable.