Andris Nelsons, who became the Boston Symphony Orchestra’s youngest music director in more than a century when he took the post in 2014, at 35, extended his contract before his first year was done through 2021-22. In February, he starts another job, as music director of the venerable Leipzig Gewandhaus Orchestra in Germany, and is embarking on an unusual collaboration between his two ensembles.

Yannick Nézet-Séguin, who became music director of the Philadelphia Orchestra in 2012, at 37, has been credited with bringing new vibrancy to its playing. He recently extended his contract there through 2026. The extension, announced when he was named the next music director of the Metropolitan Opera, reassured Philadelphia that he would not forsake them for the lures of the opera pit.

Long-Term Relationships

The Cleveland Orchestra has a contract with its music director, Franz Welser-Möst, through his 20th season, in 2022, which would give him the second-longest tenure in the ensemble’s history, after George Szell. Osmo Vanska is in his 15th season leading the Minnesota Orchestra — he briefly resigned in 2013 when the players were locked out by management — and has a contract there through 2022.

Manfred Honeck is in his 10th season with the Pittsburgh Symphony Orchestra and has a contract through 2019-20. Louis Langrée, who took over the Cincinnati Symphony Orchestra in 2013, is already on his second contract extension, through 2021-22. (And he has a newly renovated Music Hall to play in.)