Louis Sullivan, an influential American architect, is often regarded as the father of modern skyscrapers and a pivotal figure in the development of the modern architectural movement. He believed in the principle of "form follows function," emphasizing that a building's design should directly relate to its intended purpose. Sullivan's work was characterized by intricate detailing and ornamentation, which contrasted with the minimalist styles that emerged later. Sullivan's most notable contributions include the design of iconic buildings such as the Wainwright Building in St. Louis and the Auditorium Building in Chicago. His innovative use of steel frames allowed for taller structures and greatly influenced future architectural practices. He also mentored other architects, including Frank Lloyd Wright, helping to shape the next generation of American architects. Despite facing financial difficulties towards the end of his career, Sullivan's ideas and designs continue to inspire architects today. His vision for urban architecture and dedication to enhancing the built environment have left a lasting legacy in the field. Sullivan's philosophy and creativity established him as a cornerstone of modern architecture, making him a monumental figure in American design history. Louis Sullivan, known as the father of modern skyscrapers, revolutionized architecture with his belief in "form follows function." He viewed a building's design as inseparable from its purpose, which led to innovative architectural practices. Sullivan designed landmark buildings like the Wainwright Building and the Auditorium Building, where his use of steel frames facilitated the construction of taller, more dynamic structures. His work showcased a blend of ornate detailing with functional design. Though he encountered challenges later in life, Sullivan's pioneering ideas and mentorship to future architects like Frank Lloyd Wright have cemented his legacy. His contributions continue to influence contemporary architecture, reflecting his enduring impact on the field.