This publication covers the historical, technological, economic, and environmental aspects of agricultural drainage. It draws from the combined knowledge of academic and U.S. Department of Agriculture professionals in public policy, drainage theory, planning, engineering, environmental science, and economics. The main purpose is to review the evolution of modern farm drainage and to identify farm drainage objectives for agricultural extension specialists and agents, environmental specialists, drainage consultants, installation contractors, and educators. Farm production, water management, and other benefits and costs associated with the drainage of wet soils on farms are described within the context of existing USDA programs and other Federal policies for protecting wetlands.