As president of Sheila Manning Casting, Inc., Sheila Manning cast, directed, handled union matters and negotiated contracts for thousands of actors each year. She co-founded and was president of the first Association of Independent Commercial Casting Directors, and was honored with the Max Award, as well as the Media Access Award and the Seymour Heller Award.

An active public speaker, Manning was invited by UCLA to be an adjunct lecturer on acting in commercials. She served four terms as governor of the Television Academy's Commercials Peer Group and was especially proud of spearheading the successful campaign to create an Emmy for commercials.

She served as Television Academy secretary four times and chaired the Bylaws and Membership committees. In addition to her Television Academy service, she served on the board of New Leash on Life and the Synagogue for the Performing Arts.