Carl T. Shaffer was first elected president of the Pennsylvania Farm Bureau in November 2004 after serving as the organization's vice president since April, 1996. Re-elected to a third term in 2008, he leads an organization of more than 44,000 farm and rural families organized through 54 county Farm Bureaus.

Shaffer operates a 1,800-acre vegetable and crop farm in Mifflin Township, Columbia County, where he grows 1,200 acres of corn, 200 acres of wheat and 400 acres of snap beans. Among the many recognitions for leadership and achievement in agriculture, Shaffer was named as a Master Farmer in 1996, one of the highest honors awarded to farmers in the commonwealth.
 
Shaffer's grandfather and father were farmers, but Carl originally planned to go to college and pursue an off-farm career. However, an injury to his father changed his plans. As he stepped in to take over the 100-acre farm's grain and vegetable operation, Shaffer discovered he liked the farming business.  But the farm was too small to support two incomes so, with his father as co-signer, Shaffer borrowed money to buy a truck to haul fertilizer by night and deliver vegetables in the fall while working on the farm by day. When his dad retired a few years later, Shaffer hired a truck driver and took over the farm, which had expanded to 250 acres. Over the years he has continued to expand crop acreage and he still maintains a trucking business.  
 
He has served on the Pennsylvania State University Board of Trustees since 1997 and was elected to the Board of Directors of the American Farm Bureau Federation in January 2007. In 2008 he was appointed to the AFBF Foundation Board of Directors and was also elected to the AFBF Executive Committee.  He also is a member of the Board of the Pennsylvania FFA Foundation and the Agricultural Law Resource and Reference Center at Dickinson College. In 2004, he was appointed by Governor Ed Rendell and confirmed by the state Senate to serve on the Pennsylvania Farm Show Commission. Earlier he chaired the Agriculture Advisory Committee to the state Department of Environmental Protection.

Shaffer also represents the insurance programs of Pennsylvania Farm Bureau members as a member of the Board Council of Nationwide Insurance. In addition, he is president of the Pennsylvania Friends of Ag Foundation, a charitable organization supported by the Pennsylvania Farm Bureau, which works to advance public understanding and support for agriculture and agribusiness.

Past Farm Bureau leadership roles includes two years as a state Board director and service as a county board member, vice president, president and legislative chairman of the Columbia County Farm Bureau.

Past leadership with other organizations includes service as chairman of the Farm Service Agency's Pennsylvania State Committee and as a founding member of the Columbia County Crop Improvement Association. He was also a member of his local County Extension Board of Directors.