In 2004, Dio Guardi co-wrote on six of the tracks off Kelly Clarkson's sophomore album Breakaway including Clarkson's hit "Walk Away".
In July 2006, Dio Guardi was a judge in an Idol-like TV show called The One: Making a Music Star.
The show debuted on ABC with the second-lowest rating ever for a premiere on a major American network and was abruptly canceled after just two weeks.
In 2008, she was appointed to the position of executive vice president of talent development at Warner Bros.
Records, and has signed acts such as Jason Derülo and Iyaz.
Dio Guardi co-wrote the song with lead singer Tyler Connolly, and is also featured as the love interest in the music video which was released on March 10, 2009. In 2009, Dio Guardi wrote "If I Can't Have You" for Meat Loaf's 2010 album, Hang Cool Teddy Bear and recorded the vocal as a duet with Meat Loaf.