The Philadelphia study was a comprehensive economic analysis of the economy of the Philadelphia metropolitan area. The project was initially undertaken in 1963 by the Department of Regional Science, Wharton School of Finance and Commerce, University of Pennsylvania under a grant from the National Aeronautics and Space Administration under the direction of Walter Isard in association with Thomas W. Langford, Jr. and Eliahu Romanoff. At a later stage the research was carried on under the auspices of the Regional Science Research Institute through grants from the Federal Water Pollution Control Administration, U.S. Dept. of the Interior and Resources for the Future, Inc. It was initially conceived to explore the impact of NASA and other major federal activities and later extended to examine the impact of reduction in military expenditures.