Witold Roman Lutosławski (25 January 1913 – 7 February 1994) was a Polish composer and conductor. Among the major composers of the 20th century, he is "generally regarded as the most significant Polish composer since Szymanowski, and possibly the greatest Polish composer since Chopin". His compositions—of which he was a notable conductor—include representatives of most traditional genres, aside from opera: symphonies, various orchestral works, chamber works, concertos, and song cycles, some of which he orchestrated. Of these, his best known works are his four symphonies, the Variations on a Theme by Paganini (1941), the Concerto for Orchestra (1954), and a cello concerto (1970).