Anastacia (born Anastacia Lyn Newkirk) is a American singer and songwriter. Anastacia has been highly successful in Europe, Latin America, Oceania, South Africa and Australia but has not had as much success in her native United States. Despite the lack of American success, she has sold over 46 million records worldwide.

Anastacia is world renowned for her, edgy, soulful voice and is a dramatic soprano, famous for her ability to hit powerfull notes in a full voice range. Her small stature (5'3") has also led to her being nicknamed "The Little Lady with The Big Voice". She was also known for her trademark glasses (often darkly tinted), but she had surgery to correct her vision permanently in August 2005. She made headlines when diagnosed in 2003 with breast cancer. In April of 2007 she married her bodyguard of three years, Wayne Newton, in Mexico.