Oscar Niemeyer was a Brazilian architect who is considered to be one of the key figures in the development of modern architecture. Niemeyer was best known for his design of civic buildings for Brasília, a planned city which became Brazil's capital in 1960, as well as his collaboration with other architects on the United Nations Headquarters in New York City. His exploration of the aesthetic possibilities of reinforced concrete was highly influential on the architecture of the late 20th and early 21st centuries. Niemeyer continued working at the end of the 20th and early 21st century.  Over a career of 78 years he designed approximately 600 projects. He won the Pritzker price in 1988.