Premium Standard Farms, Inc (PSF), is a subsidiary of Smithfield Foods. PSF was founded in 1988 with the aim of creating a standardized method to produce premium pork. To accomplish this goal, the company decided to pursue full vertical integration—a first for pork producers in the United States. Premium Standard Farms was the second largest pork producer and the sixth largest processor in the United States until acquired by Smithfield Foods in 2007. The company is headquartered in Princeton, Missouri, with a major office in Dalhart, Texas.