GTS Radiance of the Seas is a cruise ship owned and operated by Royal Caribbean International. She is the lead ship of the Radiance class, which includes Jewel of the Seas, Brilliance of the Seas and Serenade of the Seas. All of the Radiance-class ships have a gas turbine powertrain, which produces higher efficient speeds than other cruise ships, and emissions to the air are much lower than cruise ships powered by diesel engines.

The Radiance class is a class of four cruise ships operated by Royal Caribbean built between 2001 and 2004 at Meyer Werft shipyard in Papenburg, Germany. The class was preceded by the Voyager class and succeeded by the Freedom class.