The famous architect and engineer credited with creating the first modern skyscraper is Louis Sullivan. Recognized as the "father of the skyscraper," Sullivan’s design principles emphasized the functionality and aesthetics of tall buildings. His most notable work, the Wainwright Building in St. Louis, showcased innovations in steel-frame construction and the use of large plate glass windows. Sullivan’s philosophy of form following function inspired subsequent architects and revolutionized urban landscapes, making skyscrapers a defining characteristic of modern cities around the world and forever changing architectural practice.