A survey of U.S. farmer cooperatives for calendar year 1979 showed a continuing upward trend in total business volume but a continuing decline in number of organizations and member ships. Total gross business and total net business volume are reported for 6,445 cooperatives. Business volume, number of cooperatives, and cooperative memberships are reported by commodity, by geographic region, and by State for those cooperatives classified as marketing, farm supply, and related service. A 10- year comparison shows changes in business volume, market share, and numbers. Data showing selected activities of other service organizations are also presented.