Andersen was raised in Seattle, Washington with her two older brothers. She trained as a dental assistant, although she did not like working for dentists. After she turned 30, Andersen felt that she might have the "life experience to string an entire book together."

 Her first novel, ''Shadow Dance'' was published in 1989.

Her novels are known for being funny as well as containing "sexy sizzle and great characterization." She has been nominated three times for Romantic Times Magazine's Reviewer's Choice Awards, winning in 1998 for Baby, I'm Yours. She has also been named a Romantic Times Career Achievement Award winner. She has appeared three times on the list of 10 novels picked as Amazon.com Editor's Choice (in 2001, 2002 and 2003).

Single novels

• Shadow Dance 1989/09
• Present Danger 1993/02
• Obsessed 1993/10
• On Thin Ice 1995/08
• Exposure 1996/04
• Baby, I'm Yours 1998/05
• Be My Baby 1999/03
• Baby, Don't Go 2000/05
• All Shook Up 2001/01

Marines Series

• Head Over Heels 2002/01
• Getting Lucky 2003/03
• Hot and Bothered 2004/08
• Coming Undone 2007/08

Las Vegas' showgirls Series

• Skintight 2005/07
• Just for Kicks 2006/08

The Sisterhood Diaries Series

• Cutting Loose 2008/08
• Bending the Rules 2009