The U.S. pork production sector is consolidating at an accelerating rate. In 1997, 145 firms marketing 50,000 hogs or more a year marketed 37% of U.S. hogs. This rate is up from 17% in 1994 and 7% in 1988. Most of this gain came at the expense of farms marketing fewer than 1,000 hogs a year. This segment of the industry, which has exited during previous times of poor returns, now represents only 5% of U.S. production. Liquidation of the breeding herd may be slower to occur in the future, as less significant, inefficient enterprises will be displaced. The growth plans of producers and their reported stay-in price suggest that consolidation will continue into the future.