Then as now, Back Stage was best known as a bible of theatrical casting notices. Sherry Eaker, the paper's former editor in chief, told Back Stage that Harmon's greatest contribution was going out into the theatre community to solicit those notices. "When Charlotte began," said Eaker, "people didn't know to bring casting notices in. She basically formulated the plan we have now." Ms. Harmon also worked extensively in summer stock theatre. From 1946 to 1950 she was producer-director of Chapel Playhouse in Guilford, CT, where plays she wrote were produced: Sex Is Out, Strawberries in January and You Have to Be Crazy. From there she went to Clinton Playhouse, also in Connecticut. She ran it from 1951 to 1958.

She was predeceased by her husband, press agent Lewis Harmon.

She is survived by her daughter, former actress, Jill Harmon Boyles, grandchildren Scott and Jennifer, and three great-grandchildren.