Cameron Michelle Diaz (born August 30, 1972) is a retired American actress, producer, author, and fashion model. She rose to stardom with roles in The Mask (1994), My Best Friend's Wedding (1997), and There's Something About Mary (1998), and is also known for voicing the character of Princess Fiona in the Shrek series (2001–2010). Other high-profile films include Charlie's Angels (2000) and its sequel Charlie's Angels: Full Throttle (2003), The Sweetest Thing (2002), In Her Shoes (2005), The Holiday (2006), What Happens in Vegas (2008), My Sister's Keeper (2009), Knight and Day (2010), The Green Hornet (2011), Bad Teacher (2011), What to Expect When You're Expecting (2012), The Counselor (2013), The Other Woman, Sex Tape, and Annie (all 2014).

Diaz received four Golden Globe Award nominations for her performances in Being John Malkovich (1999), Vanilla Sky (2001), Gangs of New York (2002), and There's Something About Mary (1998); for the latter, she also won the New York Film Critics Best Lead Actress Award. In 2013, Diaz was named the highest-paid actress over 40 in Hollywood. As of 2015, the U.S. domestic box office grosses of Diaz's films total over $3 billion USD, with worldwide grosses surpassing $7 billion, making her the third highest-grossing U.S. domestic box office actress (after Scarlett Johansson and Emma Watson).

Diaz is the author of two health books: The Body Book (2013), a New York Times bestseller, and The Longevity Book (2016).