Global agricultural demand spurred expansion of U.S. cropland use over the last decade to a record 391 million acres in 1981, 4 million acres more than the previous record established in 1949. The contraction of cropland use after 1949 and subsequent expansion in the seventies was accompanied by major regional shifts in the pattern of agricultural land use revealed by analysis of county data over the period 1949-78. Cropland acreage increased in the Corn Belt, Delta States, Southern Plains, and Mountain regions during 1949-78, and declined in the Northeast, Appalachian, and Southeast regions. Factors such as regional comparative advantage and natural resource development triggered regional expansion and contraction of cropland use.