NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.

Support specifically for this project was provided by the National Science Foundation and the Defense Advanced Research Projects Agency. The project also utilized resources provided to the Mapping Science Committee by the National Imagery and Mapping Agency, the U.S. Geological Survey and the Federal Geographic Data Committee, the Bureau of Transportation Statistics, the National Oceanic and Atmospheric Administration, the Bureau of Land Management, and the Bureau of the Census. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the agencies that provided support for this project.

Copies of this report are available from

Mapping Science Committee

Board on Earth Sciences and Resources

National Research Council

2101 Constitution Avenue, NW

Washington, DC 20418

Cover: Backdrop for the collage is a digital orthophoto of the Boston, Massachusetts, area. The figure was downloaded from the Internet from MIT/MassGIS Digital Orthophoto Project (see Appendix D)