Marin Alsop  (born October 16, 1956) is an American conductor and violinist. She is currently music director of the Baltimore Symphony Orchestra and chief conductor of the Vienna Radio Symphony Orchestra. In 2020 she was elected to the American Philosophical Society

Alsop was born in New York City to professional musician parents, and was educated at the Masters School. She attended Yale University, but later transferred to the Juilliard School, where she earned a bachelor's and a master's degree in violin. While studying at Juilliard, Alsop played with orchestras such as the New York Philharmonic and the New York City Ballet. She founded the string ensemble String Fever in 1981. In 1984, Alsop founded Concordia, a 50-piece orchestra specializing in 20th-century American music. She won the Koussevitzky Prize as outstanding student conductor at the Tanglewood Music Center in 1989, where she met her hero and future mentor Leonard Bernstein.

From 1993 to 2005, she was first principal conductor and then music director of the Colorado Symphony. She is now the orchestra's conductor laureate.

In the UK, Alsop has served as principal guest conductor with the Royal Scottish National Orchestra and with the City of London Sinfonia. Alsop was Principal Conductor of the Bournemouth Symphony Orchestra from 2002 to 2008, the first female principal conductor in the orchestra's history. She was voted Gramophone magazine's Artist of the Year in 2003 and won the Royal Philharmonic Society's conductor's award in the same season. Alsop received an honorary degree of Doctor of Music from Bournemouth University on 7 November 2007. Alsop served as an Artist-in-Residence at the Southbank Centre, London, for the 2011-2012 season.

In 2012, Alsop became principal conductor of the São Paulo State Symphony Orchestra (OSESP), the first female principal conductor of OSESP. In July 2013, OSESP granted her the title of music director and in April 2015 extended her contract to the end of 2019. Alsop led the orchestra on a European tour, including its first-ever appearance at the Proms in August 2012, the first Proms appearance by any Brazilian orchestra. They returned to Europe in October 2013, with concerts in Berlin, London, Paris, Salzburg and Vienna and to the Proms in August 2016. In December 2017, OSESP announced that Alsop is to stand down as its music director in December 2019, and subsequently to take the title of honorary conductor.

On 7 September 2013, Alsop became the first female conductor of the Last Night of The Proms, and returned to conduct the Last Night on 12 September 2015. On 4 September 2014, at the Proms, she was awarded Honorary Membership of the Royal Philharmonic Society.