This volume of the series "Methods in Environmental Geology," describes the feasibility of aircraft- and satellite-based methods of revealing environmental-geological problems. A balanced ratio between explanations of the methodological/technical side and presentations of case studies is maintained. The comparison of case studies from North America and Germany show how the respective territorial conditions lead to distinct methodological approaches. The dissimilarities in population density alone and often considerable differences in distances between waste disposal areas, settlements, and areas of protected groundwater necessitate a "diversified methods" approach.