Joan Marcus is a distinguished photographer renowned for her work in theatrical photography, based in Manhattan, New York City, United States. Marcus hails from Pittsburgh, Pennsylvania, and pursued her education at George Washington University in Washington, D.C. Throughout her illustrious career, primarily in Washington, D.C., and New York City, she has been dedicated to capturing the essence of Broadway theatre.

Her journey in theatrical photography began in 1986, and since then she has become an iconic figure on Broadway, photographing over a hundred shows. Some of her most notable works include capturing moments from productions such as Wicked, The Lion King, SisterAct, and The Book of Mormon. Her contributions to the field have earned her the reputation of being "one of the preeminent Broadway photographers."

Her personal life is intertwined with the Broadway community as well; she is married to Adrian Bryan-Brown, a theatrical press agent of Boneau/Bryan-Brown, a leading theatrical press agency in New York City. The power couple's involvement with Broadway theatre has led them to be recognized as one of "The 10 Greatest Broadway Couples of All Time".

In 2014, her remarkable contributions to theatre were acknowledged when she received a Tony Honor for Excellence in the Theatre at the New York Broadway Tony Awards. Her legacy extends beyond the stage as a collection of her photographs is preserved in the archives of the Billy Rose Theatre Division, New York Public Library for the Performing Arts.