The Landsat Pathfinder (now the Deforestation Mapping Group) project has demonstrated the feasibility of monitoring forest cover change over very large areas using Landsat data. To extend this approach to satisfy the needs of the Global Observations of Forest Cover will require an assessment that the overall approach successfully used in Landsat Pathfinder for the humid tropics can also be used in other regions and that more automated procedures are used. Specifically we will carry out large scale prototyping of several advanced processing procedures, including pre-processing to reduce atmospheric and MTF effects, multitemporal unsupervised processing, application of decision-tree methodologies, mixture modeling and other advanced procedures developed under previous research. We will assess the improvements they introduce using data from areas in the Pan-Amazon and Central Africa as part of the previous Landsat Pathfinder work. We will also investigate how the original Landsat methodology and the enhancements proposed operate in selected areas throughout the globe, where rapid rates of deforestation are occurring, including extra-tropical forests in South America (Paraguay), southern Africa, central Asia, sites in the Eastern United States, as well as selected sites in the boreal forest.