Erika Leonard (née Mitchell; born 7 March 1963), known by her pen name E. L. James, is a British author. She wrote the bestselling erotic romance trilogy Fifty Shades of Grey, Fifty Shades Darker, and Fifty Shades Freed, along with the companion novels Grey: Fifty Shades of Grey as Told by Christian and Darker: Fifty Shades Darker as Told by Christian; and under the name Snowqueen's Icedragon the Twilight fan fiction "Master of the Universe" that was the basis for the Fifty Shades trilogy. In 2019 her first book to not be a part of the Fifty Shades trilogy, The Mister, was published, to negative critical reception.

The Fifty Shades novels have sold over 125 million copies worldwide, over 35 million copies in the United States and set the record in the United Kingdom as the fastest selling paperback of all time. In 2012, Time magazine named her one of "The World's 100 Most Influential People." The novels were subsequently adapted into the films Fifty Shades of Grey, Fifty Shades Darker, and Fifty Shades Freed.