A native San Franciscan, Ziemienski graduated cum laude from the California College of Arts and Crafts. He is an internationally known painter, illustrator and designer. His paintings have been in numerous one man and group exhibitions and have won many awards. Dennis has taught at the California College of Arts and Crafts and the Academy of Art in San Francisco. He has had studios in California and New York. Traveling to Europe frequently, Dennis has acquired an affinity for the architecture, lifestyle and light of the Mediterranean. His strong and richly colored images borrow much of their inspiration from early 20th century paintings and posters. Churchill Downs selected Dennis as the Official Artist of the 2006 Kentucky Derby. Currently, Dennis is working on gallery shows, commissioned paintings, and murals.