The Indianapolis Symphony Orchestra is a major American orchestra based in Indianapolis, Indiana.
Annually, the Indianapolis Symphony Orchestra performs 200 concerts for over 350,000 people. It is the largest performing arts organization in Indiana. The ISO is currently one of only 18 American orchestras that perform year round. It also has a discography of 36 recordings. Since 1982, a popular summer series is the Marsh Symphony on the Prairie, performed at Conner Prairie in Fishers. It has drawn a record 13,000 attendees for the Patriotic Pops night.
The ISO's home theater is the Hilbert Circle Theatre in Downtown Indianapolis on Monument Circle. Previous locations included Clowes Hall on the campus of Butler University and Caleb Mills Hall. The Circle Theatre, a former "movie palace", was renovated and enlarged for the Symphony and re-opened October 12, 1984.
An annual holiday performance begun in December 1986 is the IPL Yuletide Celebration, hosted in recent years by Sandi Patty and Daniel Rodriguez, among others.
In 2009 the ISO announced its first-ever ensemble-in-residence Time for Three.