The first-round and total effects of untied development lending on the U.S. balance of payments are estimated for a variety of assumptions as to additionality and export procurement. A unilateral untying of development lending is estimated to cause a first-round loss of U.S. exports equal to 46 to 53 percent of the U.S. loan program. Reciprocal untying of all Development Assistance Committee (DAC) countries is estimated to produce a first-round U.S. balance-of-payments loss equal to 30 to 41 percent of the U.S. loan program if the ratio of U.S. aid to that of other DAC nations is the same as in 1969. These first-round balance-of-payments losses will be offset partly by subsequent respending by nations enjoying first-round balance-of-payments gains. The undiscounted value of these respending effects is estimated to be 7 to 15 percent of the U.S. first-round loss. In these estimates, the major source of uncertainty relates to additionality rather than to export procurement patterns. 103 pp.