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Justin Bieber is helping honour teenagers who give back to their communities.
The Baby singer will join Emma Stone, Tyra Banks and Josh Duhamel to pay tribute to young volunteers at the fourth annual TeenNick HALO Awards.
The gongs are presented to young people who are "helping and leading others".
Mariah Carey's other half Nick Cannon, who created the awards show, will serve as its host and executive producer. It is set to tape on November 17 at the Hollywood Palladium and air as a 90-minute special on the Nickelodeon cable network in the US on November 19.
The four honourees come from across the United States and range in age from 16 to 19. One started an organisation to help outfit low-income teenage girls. Another makes and distributes gift bags for breast cancer patients undergoing chemotherapy.
