The designer will be a consultant on the live finals of the series - beginning next Thursday (15.03.12) - to ''help guide the finalists style transformations as they fight for their chance to become the next American Idol.''
He said: ''I am honoured to be joining the 11th season of 'American Idol'.
''My own experiences at the beginning of my career inspired my commitment to mentor young people who are dedicated to pursing their dreams. I look forward to working with the artists to guide them in defining their performance style and identity.''
Tommy has been closely linked to music throughout his career, from styling his brother's band when he was 18, to dressing stars including Lenny Kravitz, Britney Spears, The Rolling Stones, Taylor Swift and Beyonce. He also frequently uses rock tracks to back his fashion shows.