Kara DioGuardi

Songwriter and producer Kara DioGuardi joined Simon Cowell, Paula Abdul and Randy Jackson at the judging table for the eighth and ninth seasons of "American Idol." She is no longer a judge on the Fox program. Although not a household name when she was selected for the show, DioGuardi has worked with Christina Aguilera, Gwen Stefani, Kylie Minogue and Carrie Underwood.