A partial-equilibrium, multiple-commodity, multiregion model of agricultural policy and trade is used to simulate the effects of changes in domestic and trade policy on dairy production, consumption, prices, and trade. Simulations using the ERS-Penn State Trade model analyze the effects of separately and concurrently relaxing domestic income and price supports, and import restrictions and export subsidies, with special attention to tariff-rate and milk production quotas. Modeling results indicate that liberalization would reduce world dairy product supplies and increase the value of dairy trade.