Conductor and pianist William Kelley was Kapellmeister at Theater Bremen until 2024, where he conducted productions of Salome, Orpheus in der Unterwelt, Doctor Atomic, Macbeth, Il Barbiere di Siviglia, Angels in America (Eötvös), Jenufa, Pagliacci, The Cunning Little Vixen, King Arthur (Purcell), and Hello, Dolly! as well as family and gala concerts with the Bremer Philharmoniker.

In 2023, he made his debut at the Hamburgische Staatsoper with Bizet’s Carmen and returned in 2024 for Cosí fan tutte and musical meets opera, an open-air concert at Jungfernstieg hosted by Staatsoper Hamburg and the Hamburg Filmfest. He also returns to his alma mater in 2024 to conduct Le Nozze di Figaro at The Juilliard School. As a coach and educator, Kelley works regularly with young singers and pianists at the Dutch National Opera Studio in Amsterdam.

Previously, Kelley held the position of Kapellmeister at Luzerner Theater in Luzern, Switzerland. He made his European conducting debut in 2017 with the Luzerner Sinfonieorchester and Mozart's Die Zauberflöte with following productions including the Swiss premiere of Abraham’s Märchen im Grand Hotel, Mozart's Don Giovanni, Carmen.maquia (version for ballet), Piazzolla’s María de Buenos Aires, a world premiere in the Lucerne Festival: Im Amt für Todesangelegenheiten (2018) with the 21st Century Orchestra, and the 2019 Gübelin Luzerner Sinfonieball.

As a guest conductor, Kelley has appeared at the Hamburgische Staatsoper, Prague Radio Symphony, assisted Christopher Franklin with the Czech Philharmonic and Yoel Gamzou in Seven Deaths of Maria Callas with Marina Abramović at Teatro San Carlo. As a pianist and vocal coach, Kelley worked for institutions such as The Dutch National Opera, The Lindemann Young Artist Program at The Metropolitan Opera, The Juilliard School, the Czech Philharmonic, and the Luzerner Sinfonieorchester, and with conductors such as James Gaffigan, Edward Gardiner, Fabio Luisi, Yannick Nézet-Séguin, and Lorenzo Viotti. Since 2020, he has enjoyed a close collaboration with English composer Iain Bell and gave the world premiere of his melodrama for tenor and piano, Comfort Starving with tenor, Petr Nekoranec and a staged version of the piece later that summer at the Bach Festival Swidnica with director, Krystian Lada. His collaboration with Bell and Lada continued in 2021 with a staged performance of the partner-work to Comfort Starving, The Man With Night Sweats for baritone and piano at the Opera Rara festival in Krakow, Poland. Previous performance highlights include recitals with tenor, Petr Nekoranec at Staatsoper Stuttgart and the Janacek Festival in Ostrava, Czech Republic, Schubert’s Winterreise with baritone, Christopher Herbert on Trinity Wall Street’s Twelfth Night Festival and the Harvard Club, a residency with the New York Festival of Song (NYFOS) at the Caramoor Festival and his Lincoln Center debut with a recital in Alice Tully Hall alongside baritone, Theo Hoffman, which included the New York premiere of Jonathan Dove’s song set, Three Tennyson Songs [2011].

Kelley is a graduate of The Juilliard School and The University of North Carolina Greensboro. He is currently based in Amsterdam.