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Rockstar Advanced Game Engine (RAGE), is a game engine created by a small team called the "RAGE Technology Group" at the video game developer Rockstar San Diego with contributions by Rockstar North. Rockstar developed the engine to facilitate game development on the PC, PlayStation 3, Wii, and Xbox 360 consoles. RAGE evolved from the Angel Game Engine developed by Angel Studios for use in the sixth generation console era versions of the Midnight Club series and other Angel Studios games.

Rockstar has integrated several third party middleware components into RAGE, like the proprietary Euphoria character animation engine, the open source Bullet physics engine and the proprietary SpeedTree virtual foliage system.

Prior to RAGE, Rockstar mostly used Criterion Games' RenderWare Engine to develop various game titles, including the PlayStation 2, Xbox, and PC installments of the Grand Theft Auto franchise. The PSP versions and later ports of the Grand Theft Auto 'Stories' games however, were built on RAGE. Development of RAGE was a reaction to the acquisition of Criterion by video game conglomerate Electronic Arts. Rockstar chose not to license the RenderWare engine, due to concern over the information gathering clause in EA's license agreement.