From the back cover:
What's a fantasy role-playing game without monsters? At the heart of any good AD&D adventure, you'll find great monsters -- dragons, giants, trolls, killer oozes, shadows, and who knows what else! This first Monstrous Compendiium gives DMs and players 144 5-hole punched pages of new and improved monsters, with all-new illustrations, expanded descriptions, and complete statistical data, all in an easy-to-read, easy to reference format. Players can organize the monsters in this pack, alphabetically, according to when they show up in an adventure, according to monster type, or any other way they see fit. And the binder is large enough to hold additional monster sheets from Monstrous Compendium Volumes Two and Three!