The evolution of forest sector models in the United States from simple Malthusian concepts of catastrophic scarcity to integrated planning models has been guided by (and in response to) changing policy contexts. This evolution is described both in terms of changing model forms and changes in the projections of future market prospects for forest products. In addition, variations of forest sector models have been used in the last 15 years to look at increasing environmental regulation on timber production in the United States. Three issues are examined : the economic impacts of reductions in National Forest harvest, the economic consequences of environmental regulations on private timberland, and the impact of a log export ban on lumber production in the Pacific Northwest.