I Am... Sasha Fierce is the third studio album by American singer Beyoncé. It was released on November 12, 2008, by Columbia Records and Music World Entertainment. In its original release, the album was formatted as a double album, intending to market Beyoncé's dichotomous artistic persona. The first disc I Am... contains slow and midtempo pop and R&B ballads, while the second, Sasha Fierce (named after Beyoncé's on-stage alter ego), focuses on more uptempo beats that blend electropop and Europop elements. In composing the songs' lyrics, Beyoncé worked with writers, with each session accompanied by live orchestration.

Beyoncé credited both her husband—rapper Jay-Z—and jazz singer Etta James for inspiring her to push the limits of her songwriting and artistry. Musically, I Am... drew inspiration from folk and alternative rock, while blending acoustic guitar elements into contemporary ballads, and its tracks were written and produced by Beyoncé, during collaborative efforts with Babyface, Tricky Stewart, The-Dream and Ryan Tedder. Sasha Fierce boasted production from Darkchild and Sean Garrett.

I Am... Sasha Fierce received mixed to positive reviews from music critics and was a massive commercial success, debuting at number one on the US Billboard 200 chart with first-week sales of 482,000 units and earning Beyoncé her third consecutive US number-one solo album. The album has earned one diamond and over thirty platinum certifications in separate worldwide markets, being certified six-times platinum by the Recording Industry Association of America (RIAA) after shipping over six million units in the United States. I Am... Sasha Fierce has sold 10 million copies worldwide, making it one of the best-selling albums of the 21st century. The album garnered seven Grammy Award nominations at the 52nd Annual Grammy Awards ceremony (2010), including a nomination for Album of the Year, winning six—the most awards won in one night by a female artist.