Eero's career began in his father's office, with whom he designed the Smithsonian Art Gallery in Washington (1939) and the 25-building General Motors Technical Center in Michigan (1945-1955). After his father died in 1950, Eero continued his career as an architect, producing works characterised by a very personal language, a sort of Mies van der Rohe rationalism mixed with fluid Scandinavian organic forms. The soft lines and sculptural shapes that characterise the TWA terminal at John F. Kennedy International Airport in New York (completed posthumously in 1962) perfectly represent Saarinen's approach. The building was awarded the Gold Medal by the American Institute of Architects.
In parallel with his work as an architect, Saarinen pursued a career as a designer with a similar approach. The sculptural lines and organic shapes that characterise Saarinen's work derive from the synthesis of art and technology, achieved through years of experimentation with materials and production techniques. One example of Saarinen's vision is the Organic Chair, designed with his friend Charles Eames and first prize winner of the design competition organised by MoMa in New York in 1940. The chair was not immediately produced due to technical difficulties but later, the German company Vitra was able to manufacture it. Thanks to his collaboration with Knoll, Saarinen's visionary proposals were mass-produced in the 1950s, leading to the creation of such iconic objects as the Tulip collection (1955), which includes the Tulip Chair and the Tulip Table, and the Womb collection of upholstered armchairs (1948) designed with Florence Knoll. His untimely death in 1961 halted the production of other furnishings created for building interiors he had also designed, including Lounge Seats for the General Motors Technical Center, modular seating for the Law School at the University of Chicago and tables for Vassar College.