Conductor William Lacey was born in London in 1973, and became a German citizen in 2017. He trained initially as a pianist, studied chamber music with Alfred Brendel and György Kurtágand graduated from King's College, Cambridge with a first-class degree in music. He then spent three years in London, working as a conductor, pianist and coach, and concentrating especially on contemporary music. He began his international career as the Staff Conductor at San Francisco Opera, from 1998 to 2001. At San Francisco he conducted nine different operas (including "Aida", "La Boheme" and "The Tsar's Bride"), and assisted Mackerras, Gergiev and Runnicles (notably on "The Ring", "Parsifal" and "Tristan und Isolde"). Later he spent three years as Erster (koordinierter) Kapellmeister at the Oper Leipzig. In this position he conducted over one hundred performances of a very wide repertoire with the Leipzig Gewandhaus Orchestra, one of the oldest and most tradition-rich orchestras in the world. His Leipzig performances included "Hänsel und Gretel", "Aufstieg und Fall der Stadt Mahagonny", "Die Fledermaus", "Die Zauberfloete", "The Cunning Little Vixen", "Macbeth", "La Traviata" and "La Boheme", as well as "Cinderella" by Prokofiev. 

William Lacey is now internationally active as a guest conductor. He has performed regularly with Plácido Domingo, including “Tamerlano” in Barcelona, Washington, and Los Angeles, and "Iphigénie en Tauride" in Washington. In collaboration with Graham Vick and his inspirational Birmingham Opera Company, he has conducted new productions of "Fidelio", "Idomeneo" and "Don Giovanni", and the world premiere of Jonathan Dove's "Life is a Dream". He recently conducted "Jenufa" for the first season of Grange Park Opera's new theatre at West Horsley. 

Lacey has often conducted the music of Benjamin Britten, and in 2013 he led a highly acclaimed new production of "Curlew River" with Ian Bostridge at the Barbican Centre in London. In 2012 he conducted the first Moscow performances since 1965 of “A Midsummer Night’s Dream”, in Christopher Alden’s production from ENO, at the Stanislavsky Opera. This production won the 2013 Golden Mask for Best Opera. Lacey subsequently made his debut at the Bolshoi with "Le Nozze di Figaro" in concert, and his debut at the Tchaikovsky Concert Hall. He also conducted two concert programmes with the Bolshoi Orchestra (Mozart, Rachmaninov, Stravinsky and Richard Strauss) on tour in the St Petersburg Philharmonic Hall.  In 2014 he returned to the Stanislavsky for a new production of "Don Giovanni", and in 2015 he conducted the Bolshoi's first new production of "Le Nozze di Figaro" in twenty years. In November 2016 he returned to the Bolshoi to conduct the hugely successful Moscow premiere of "Billy Budd", directed by David Alden, and he continues to conduct "Figaro" there regularly. 

In North America, William Lacey has conducted regularly at many of the leading opera companies, including Houston Grand Opera, Los Angeles Opera, Santa Fe Opera, Washington National Opera, the Canadian Opera Company in Toronto, New York City Opera, Utah Opera, Hawaii Opera Theatre, and Glimmerglass Opera. 

His guest appearances in European opera houses have included the Gran Teatre del Liceu in Barcelona, the Opéra Comique in Paris (with l'Orchestre de Paris), the Royal Opera in Stockholm, Norwegian National Opera, Bergen International Festival, English National Opera, Greek National Opera, Cologne Opera, Opera North, Nationale Reisopera (on tour throughout the Netherlands), Nordnorsk Opera, Scottish Opera, Grange Park Opera, and Garsington Opera.

William Lacey has wide experience as a concert conductor, having appeared in concert with the Houston Symphony Orchestra, the Pacific Symphony Orchestra, the Hong Kong Philharmonic Orchestra, the Youth Orchestra of Bolivia Clasica (La Paz), the Israel Camerata, the Arctic Philharmonic, the Bolshoi Orchestra, the Musica Viva Orchestra (Moscow), the Collegium Musicum of Copenhagen, the Leipzig Gewandhaus Orchestra, the Munich Radio Orchestra, the Wuppertal Symphony Orchestra, the Augsburg Philharmonic, the Tiroler Festspiele Orchester, the Scottish Chamber Orchestra, the Royal Scottish National Orchestra, the Ulster Orchestra,  l'Orchestre de Bretagne, the Real Filharmonia de Galicia, the Orquesta Sinfonica de Navarra, the Remix Orchestra at the Casa da Musica in Porto, the Haydn Orchestra of Bolzano, and the Orchestra of the Teatro Massimo Bellini in Catania.