In 1907 Dr. Seaman Knapp, an agriculturist and special agent employed by the USDA, engaged David Nicholas Barrow to set up a farm demonstration program to instruct farmers in proper farming techniques. Barrow worked in several states east of the Mississippi River and in South Carolina employed two district agents and several county agents.

Intended initially for farmers, the program at Clemson soon grew to include rural youth and women; O. B. Martin headed the boys program and Marie Cromer Siegler began a home demonstration program for women and a tomato club for girls. (These programs were the precursors to the 4-H Club.)

Barrow served as superintendent of extension until 1909. His successors were William R. Perkins and Joseph N. Harper, specialists in agriculture. During these years, Extension work was administered through the South Carolina Agricultural Experiment Station.

With the growth of extension work came demands for Clemson College and the State of South Carolina to provide financial assistance. The Rockefeller Foundation granted funds to be used for these activities, but the amount of aid was insufficient for the increasing demand for information and instruction. Relief came in 1914 when Congressman A. F. Lever sponsored legislation to establish a national extension service; Congress passed the Smith-Lever Act which empowered the government with the responsibility to fund and operate these programs that Knapp and others had worked to establish. As a result of the passage of the Smith-Lever Act, extension work in South Carolina was carried on in conjunction with Clemson College and the USDA; the administrative branch of the service being located at Clemson and the Home Demonstration branch located at Winthrop College in Rock Hill. In 1914, William W. Long was appointed as director of the Extension Service; he served as Director until November 1934.

By 1930 a county agent and a home demonstration agent, and in many counties subject specialists, had been appointed for each county in the state. After World War II, the role of the Extension Service expanded to address the concerns of urban as well as rural dwellers. To fulfill this role, the Extension Service, under the direction of W. W. Long (1914-1934), D. W. Watkins (1934-1955), George B. Nutt (1955-1969), Wayne T. O'Dell (1969-1984), and Bud Webb (1984-present) disseminated information on hundreds of topics, for example, financial management, consumerism, and health and nutrition. Although the service functioned as part of the National Cooperative Extension Service, activities within the state of South Carolina were determined by extension advisory boards on which local citizens served.