The Economic Research Service (ERS) published bST and the Dairy Industry: A National, Regional, and Farm-level Analysis in 1987. In 1989, ERS was requested to update and extend the study. The following findings of the earlier study remain valid: effects of bST on the dairy industry would not be as dramatic as originally projected; changes underway in the industry would be reinforced but not significantly changed with bST adoption; and industry effects of bST ultimately depend on the flexibility of the dairy price support program. Current international dairy market conditions are different than those of the 1987 study. Attitudes toward bST in other milkproducing countries have been generally unfavorable. Liberalized agricultural trade could lead to greater participation by the United States in international dairy trade but whether international buyers would purchase products containing milk from bST-treated animals is unknown.