She began her acting career appearing on Broadway as Irene Molloy in the 1967 all-black version of Hello, Dolly!

[1][4] Of African American heritage, Yancy was born and raised in New York City and began working as a model before acting and singing.

[5] Yancy made her screen debut playing minor role in the 1968 comedy film What's So Bad About Feeling Good?.

[2] On television, Yancy guest-starred in a more than 30 shows, including Love, American Style, Sanford and Son, Starsky & Hutch, Diff'rent Strokes, Picket Fences, The Practice, Frasier, How to Get Away with Murder and Criminal Minds.

In 2018, Yancy played Gayla, the housekeeper of Patricia Clarkson's character, in the HBO miniseries, Sharp Objects.