Johnston dedicated himself to sculpture after earning a B.S. in architecture from Georgia Institute of Technology. He then studied at the Pennsylvania Academy of Fine Arts, the National Academy of Design and the Enzo Cardini and Romanelli Studios in Florence. Completed sculptural commissions include "Wedlock" for Lafayette Centre, Washington, D.C.; “Faith, Hope and Love” in Washington State; "The Healer" for the Govan's Church park in Baltimore; a bronze relief for Notre Dame College of Baltimore; and "Joy" for White River Medical Center in Arkansas. Other commissions include "First from the Sea and First to the Stars" for Hampton, Virginia’s City Hall, and "Mother and Child," a fountain centerpiece for the Evanston Woman’s Hospital in Illinois. In 1996, the Washington National Cathedral commissioned a figure of El Salvador’s Archbishop Oscar Romero and the People’s Republic of China invited Mr. Johnston to create "Yin/Yang" for Weihai, Shandong Province.