After graduating from Hargrave High School in Huffman, Texas in 1991, he attended Galveston College and Lewis-Clark State College in Idaho. He began his career in the minor-league system of the San Francisco Giants, but was traded to the Chicago White Sox in 1997 for starting pitchers Wilson Alvarez and Danny Darwin, along with top reliever Roberto Hernandez. Foulke was granted free agency on October 27, 2003.