Marianne Challis, an award-winning cabaret singer and one of Broadway's busiest voice teachers, died Aug. 29 at her apartment and voice studio in Manhattan. She was 58.

Ms. Challis was a sought-after vocal technician. She primarily taught Broadway performers, and also worked for organizations such as Disney Productions and Lincoln Center for the Performing Arts.

Ms. Challis was a graduate of Eastern Illinois University in Vocal Performance and Music Education. She also studied with the Opera Department of Northwestern University and at Guthrie Theater. She was an Associate Professor of Vocal Studies at the University of Hartford's Hartt School and served as a consultant to their musical theatre program.

In Connecticut, Ms. Challis and her husband operated Broadway Boot Camp, a workshop for young actors and musical theatre performers through their Southport Studio Theater program.

As a cabaret singer, her shows included "America’s Favorite Middle-Aged Party Girl." She played such halls as the Royal Room in Palm Beach, Feinstein's at the Regency, the Laurie Beechman Theater in NYC and Playhouse on the Green in Bridgeport, CT. In 2008 she won a Bistro Award for Outstanding Female Vocalist.

Her early career was in the musical theatre. In her twenties, she toured the country in the Hermione Gingold production of Side by Side by Sondheim. She also appeared in many regional productions. Her final theatre performances were starring as Nellie Forbush in the New York City Opera production of South Pacific.

Ms. Challis is survived by her husband of 30 years, Frank Root, son Lonnie and daughter Abby.

There will be a memorial service on Sept. 2 at 1:30 PM at Southport Congregational Church, 524 Pequot Avenue, Southport, CT. A memorial celebration in New York City is planned at a later date.