Her success continued with the release of her sophomore album, "Oops!... I Did It Again" in 2000, which established her as a pop icon and credited for influencing the revival of teen pop in the late 1990s.

In 2001, she released "Britney" and played the starring role in the film "Crossroads". She assumed creative control of her fourth studio album, "In the Zone" released in 2003, which made her the only female artist of the Nielsen Soundscan era to have her first four albums debut at number one. Her fifth studio album, "Blackout" was released in 2007. Her sixth studio album, "Circus" released in 2008, also debuted at number one in the Billboard 200 albums chart with the hit single Womanizer which is Spears second song to peak at number one on Billboard Hot 100 in over 10 years. In the late 2009, Spears released The Singles Collection which include Spears third number one hit single entitled 3.

According to Zomba Label Group and Sony Music, Spears has sold over 85 million records worldwide. On December 11, 2009 Billboard Magazine named Spears the second-best selling act of the 2000s, solely based on album sales as well as the 8th overall best act of the decade based on album sales, chart success, and cultural relativity. She is ranked as the eighth best-selling female recording artist in the U.S. with 32 million copies of her albums certified by the Recording Industry Association of America (RIAA), and is currently the fifth best-selling artist of the decade in the country, as well as the top-selling female artist. Spears is also ranked by "Forbes" 2009 issue as the 13th most powerful celebrity, and with earnings of over $35 million dollars in 2009, the 2nd-highest earning young musician of the year. According to Billboard, Spears has four of her albums among the top 20 biggest-opening-week albums of the decade.