Until now, altitude has not been taken into account when estimating tropical arthropod diversity. This book presents the first taxonomic results of an unprecedented terrestrial biodiversity survey on Papua New Guinea’s Mount Wilhelm designed to do just that. Not only is Mount Wilhelm the nation’s tallest peak at 4,509 meters above sea level, it is also one of the few equatorial mountains outside the Andes that still possesses continuous, undisturbed forest from sea level up to the timber line, presenting many unique opportunities. Arthropods were collected by various methods at eight different elevations, with a botany survey also conducted at each elevation to characterize vegetation. Results of the survey included, among others, new species discovery, direct financial benefits to landowner communities, raised profile of conservation areas, and the generation of crucial biodiversity information needed for ecological analyses and conservation management.