Chicago a cappella is a classical vocal ensemble that moves the heart and spirit with fun, innovative concerts. Founded by Jonathan Miller in 1993, Chicago a cappella is recognized as one of the area's most accomplished and innovative vocal ensembles. Spanning a repertoire from Gregorian chant to the Beatles and beyond, the group is known for its performances of early music, vocal jazz, and spirituals, as well as a special focus on music written in the present generation. The ensemble has introduced dozens of works to Chicago audiences for the first time, including commissioned works by Chen Yi and Tania Leon.

Chicago a cappella has toured to 11 U.S. states and Mexico and has appeared on national radio broadcasts, including American Public Media's Performance Today. Its discography includes recordings on the Cedille and Centaur Records labels, including highly-acclaimed CDs of Renaissance and contemporary works.

Performing most usually with an ensemble of nine singers, Chicago a cappella presents a series of concert programs each year in Chicago, Evanston, Naperville, and Oak Park, IL. In 2010-11, the ensemble celebrates its 18th season under founding Artistic Director Jonathan Miller, with musical preparation by Music Director Patrick Sinozich.