In the US, Judd was an assistant conductor of The Cleveland Orchestra, and served as associate music director of the European Union Youth Orchestra. Judd made his U.S. opera debut in 1988 conducting Don Giovanni for the Florida Grand Opera. Judd was the last full-time music director of the Florida Philharmonic, from 1987 to 2001. In 2013, Judd was appointed music director of The Little Orchestra Society. Judd is the founder of Miami Music Project, a non profit organization, which provides music education to children inspirated on an El Sistema-style model.
Judd served as music director of the New Zealand Symphony Orchestra (NZSO), the first NZSO conductor with that title, from 1999 to 2007. He conducted several recordings with the NZSO for the Naxos label, and led the NZSO in its first-ever appearance at The Proms in August 2005. Judd now holds the title of Music Director Emeritus of the NZSO.
In 2014, Judd became music director of the Israel Symphony Orchestra Rishon LeZion. He offered to waive his salary in 2015, in the wake of financial difficulties at the orchestra. In September 2016, Judd was appointed artistic director and principal conductor of the Daejeon Philharmonic Orchestra in Korea. He became chief conductor of the Slovak Philharmonic Orchestra as of the 2017–2018 season. He is scheduled to conclude his chief conductorship of the orchestra as of the close of the 2020–2021 season.
- Edward Greenfield (9 April 2004). "Elgar: Wand of Youth Suites nos 1 and 2; Nursery Suite; Dream Children: NZSO/Judd". The Guardian. Retrieved 4 March 2009.
- Anthony Holden (18 July 2004). "Bridge, Orchestral Works". The Observer. Retrieved 4 March 2009.
- George Hall (20 August 2005). "Prom 46: New Zealand Symphony/ Judd (Royal Albert Hall, London)". The Guardian. Retrieved 4 March 2009.
- Zuzana Vilikovská (3 November 2017). "James Judd: Whether it is orchestral music, jazz or rock – music is music". Slovak Spectator. Retrieved 7 July 2018.
- "Slovenská filharmónia pod taktovkou Daniela Raiskina" (Press release). Slovak Philharmonic. 12 November 2019. Retrieved 24 November 2019.
- Tim Smith (1 February 1998). "Raising Florida's Musical Pulse". New York Times. Retrieved 4 March 2009.