Brönnimann was born in Switzerland, studied at the Musik-Akademie der Stadt Basel and was a Junior Fellow in Conducting at the Royal Northern College of Music in Manchester. From 2008-2012, Brönniman was the Music Director of Colombia's National Symphony Orchestra, and from 2011-2015, he was Artistic Director of Norway's BIT20 Ensemble. Brönnimann is currently Principal Conductor of Orquestra Sinfonica do Porto Casa da Música and Principal Conductor of the Basel Sinfonietta.
Guest conducting engagements have included Frankfurt Radio Symphony, WDR Symphony, Vienna Radio Symphony, Royal Stockholm Philharmonic, Seoul Philharmonic Orchestra, Philharmonia Orchestra, Bergen Philharmonic Orchestra, BBC Philharmonic Orchestra.
Brönnimann is committed to contemporary music and has championed the music of composers such as Harrison Birtwistle, Unsuk Chin, Thomas Ades, John Adams, Kaija Saariaho, Helmut Lachenmann, and Magnus Lindberg.
He also conducts in the opera house, having made his operatic debut with English National Opera in 2008 with Olga Neuwirth Lost Highway since which time he has returned to ENO for productions of John Adams Death of Klinghoffer (Tom Morris) and La Fura dels Baus’s Ligeti Le Grand Macabre, a work which he also conducted at the Teatro Colón, Argentina, and at Komische Oper Berlin in the Barrie Kosky revival in 2013. He has also conducted in the Komische Oper Berlin, Teatro Colón, and the Norwegian Opera.
Brönniman has recorded two CDs. In 2012, AO Vivo, a recording of works by Pascal Dusapin, with the Orquestra Sinfónica do Porto Casa da Música and the Remix Ensemble, and in 2017, György Ligeti's Concertos & Melodien, with the BIT20 Ensemble.