Gloria Shayne Baker, born Gloria Adele Shain on September 4, 1923, in Brookline, Massachusetts, was an American composer and songwriter renowned for her contribution to the Christmas carol "Do You Hear What I Hear?" in 1962, alongside her then-husband Noël Regney. Raised in a Jewish family, she was the daughter of Attorney Mark Shain and Professor Rose Wies Shain and grew up next to the Kennedy family. She began her music career with her sisters as part of The Shain Sisters singing trio. Gloria altered her surname to Shayne for professional purposes and earned a bachelor's degree from the Boston University School of Music.

During the 1940s, Shayne relocated to New York City, where she worked as a pianist and arranged music for notable composers like Stephen Sondheim and Irving Berlin. She met Noël Regney in 1951, and they married the same year, collaborating on several songs, with Shayne typically writing lyrics and Regney composing music. Their notable works include "Rain Rain Go Away," "Sweet Little Darlin'," and "Another Go Around." Shayne also achieved success independently, composing "Goodbye Cruel World" and co-writing "Almost There."

"Do You Hear What I Hear?" was created during the Cuban Missile Crisis as a plea for peace, with Regney writing the lyrics and Shayne composing the music. The song became a hit after being recorded by the Harry Simeone Chorale and later by Bing Crosby. It has since been covered by numerous artists.

Shayne married her second husband, William Baker, in 1973. She passed away from lung cancer on March 6, 2008, in Stamford, Connecticut, at the age of 84.