Ecological change is constant and profound, yet it often occurs at temporal and spatial scales that are difficult to measure and interpret. This publication demonstrates how diverse data bases, archived in different formats and at numerous locations, can be brought together to provide an integrated perspective on the relationship between land use and landcover change. The authors provide the historical context for interpreting recent landcover change in several regions of North America and articulate the value of a comprehensive continental land-use history for guiding environmental policy and management decisions during the coming century and beyond.