Martha Helen Stewart (born August 3, 1941) is an American retail businesswoman, writer, and television personality. As the founder of Martha Stewart Living Omnimedia, she gained success through a variety of business ventures, encompassing publishing, broadcasting, merchandising and e-commerce. She has written numerous bestselling books, was the publisher of Martha Stewart Living magazine and hosted two syndicated television programs: Martha Stewart Living, which ran from 1993 to 2004, and The Martha Stewart Show, which ran from 2005 to 2012.

Stewart was convicted of felony charges related to the ImClone stock trading case; she served five months in federal prison for fraud and was released in March 2005. There was speculation that the incident would effectively end her media empire, but in 2005, Stewart and her company returned to profitability in 2006. In 2024, at the age of 81, Stewart became the oldest woman to appear on the cover of Sports Illustrated Swimsuit Issue magazine.