Fauquier County is located in northern Virginia approximately 40 miles west of Washington, D.C. The county is large by Virginia standards (660 square miles). The 1990 Census led to the official designation of Fauquier County as part of the Washington-Baltimore Metropolitan Area. The forces of land use change are coming from the east as the metropolitan area expands, seemingly inexorably, outward. In 1850, Fauquier County had a recorded population of 20,868. One hundred years later in 1950, the census showed growth to only 21,248. During the next 40 years, the population would more than double and today the estimated population exceeds 52,000. The growth in population has been attributable to net migration—defined as the number of persons who moved in minus the number of persons who moved out. Net migration has been influenced primarily by exogenous variables in the expanding metropolitan region. Fauquier County may be able to have more influence on where new residents locate than on the rate of migration.