Chicago performing arts critic.

Claudia Cassidy was born in 1900 in the port town of Shawneetown, IL, where she first encountered the performing arts on show boats that cruised the Ohio River. When she was 14, Cassidy's parents George and Olive moved the family to Champaign, IL. After graduating from the University of Illinois in 1921, Cassidy worked as a secretary at the Chicago Journal of Commerce, where she moved into theater criticism after an editor, looking for someone to write a last minute review, spotted her in the office. Her sharp, opinionated writing style attracted many fans, and her column became an important feature of the Journal.

In 1941 she moved on to a larger audience at the Chicago Sun, but left after a year for the Chicago Tribune at the behest of publisher Robert R. McCormick. While at the Tribune, Cassidy wrote her "On the Aisle" commentary as well as other reviews and articles steadily until 1965, and beginning in 1949 made annual summer tours of European festivals for "Europe on the Aisle."

After 1965, Cassidy wrote on a free-lance basis for the Tribune, Chicago Magazine, and other publications, and from 1968 to 1983 she hosted a weekly radio program of arts criticism on Chicago's WFMT-FM.

Cassidy, sometimes referred to as "Acidy Cassidy," was an influential presence on the Chicago theater scene, particularly from 1942-1965 when her Tribune byline was a consistent feature in the paper. Her writing alienated and angered some in the arts community, but her praise also promoted the careers of others, including Tennessee Williams, Lotte Lehmann, and Maria Callas. Cassidy fiercely supported Williams' "The Glass Menagerie," which premiered at Chicago's Civic Theatre in 1944. She also strongly influenced events at the Chicago Symphony Orchestra, where her public admiration or disdain of music directors had a direct effect on the CSO's history.

Cassidy was married to William J. Crawford for 57 years. After his death in 1986, she retreated from public life and lived alone at the Drake Hotel. Her last published writing was for the 1990-1991 Lyric Opera program book. She died after a brief illness on July 21, 1996.