Mstislav Leopoldovich "Slava" Rostropovich (Russian: Мстисла́в Леопо́льдович Ростропо́вич, Mstislav Leopol'dovič Rostropovič, pronounced [rəstrɐˈpovʲɪtɕ]; 27 March 1927 – 27 April 2007) was a Soviet and Russian cellist and conductor. He is considered to be one of the greatest cellists of the 20th century. In addition to his interpretations and technique, he was well known for both inspiring and commissioning new works, which enlarged the cello repertoire more than any cellist before or since. He inspired and premiered over 100 pieces, forming long-standing friendships and artistic partnerships with composers including Dmitri Shostakovich, Sergei Prokofiev, Henri Dutilleux, Witold Lutosławski, Olivier Messiaen, Luciano Berio, Krzysztof Penderecki, Alfred Schnittke, Norbert Moret, Andreas Makris and Benjamin Britten.

Rostropovich was a huge influence on the younger generation of cellists. Many have openly acknowledged their debt to his example. In the Daily Telegraph, Julian Lloyd Webber called him "probably the greatest cellist of all time."

Rostropovich either commissioned or was the recipient of compositions by many composers including Dmitri Shostakovich, Sergei Prokofiev, Benjamin Britten, Henri Dutilleux, Olivier Messiaen, André Jolivet, Witold Lutosławski, Luciano Berio, Krzysztof Penderecki, Leonard Bernstein, Alfred Schnittke, Aram Khachaturian, Ástor Piazzolla, Andreas Makris, Sofia Gubaidulina, Arthur Bliss, Colin Matthews and Lopes Graça. His commissions of new works enlarged the cello repertoire more than any previous cellist: he gave the premiere of 117 compositions.

Rostropovich is also well known for his interpretations of standard repertoire works, including Dvořák's Cello Concerto in B minor and Haydn's cello concerti in C and D,[citation needed] Prokofiev's Symphony-Concerto and the two cello concerti of Shostakovich.

Between 1997 and 2001 he was intimately involved in the development and testing of the BACH.Bow, a curved bow designed by the cellist Michael Bach. In 2001 he invited Michael Bach for a presentation of his BACH.Bow to Paris (7ème Concours de violoncelle Rostropovitch). In July 2011, the city of Moscow announced plans to erect a statue of Rostropovich in a central square, and the statue was unveiled in March 2012.

He was also a notably generous spirit. Seiji Ozawa relates an anecdote: on hearing of the death of the baby daughter of his friend the sumo wrestler Chiyonofuji, Rostropovich flew unannounced to Tokyo, took a 1 1/2 hour cab ride to Chiyonofuji's house and played his Bach sarabande outside, as his gesture of sympathy—then got back in the taxi and returned to the airport to fly back to Europe.