Grand Theft Auto 4 took more than three and half years to create

With over 1000 people working on it.

at a cost of almost $100 million

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.

Euphoria is a game animation engine created by NaturalMotion based on Dynamic Motion Synthesis, NaturalMotion's proprietary technology for animating 3D characters on-the-fly "based on a full simulation of the 3D character, including body, muscles and motor nervous system". Instead of using predefined animations, the characters' actions and reactions are synthesized in real-time; they are different every time, even when replaying the same scene. While it is common for current video games to use limp "ragdolls" for animations generated on the fly, Euphoria employs a more complex method to animate the entirety of physically-bound objects within the game environment.

Bullet is an open source software multi-threaded 3D collision detection, soft body and rigid body dynamics library (physics engine) for games and visual effects in film .

Image Metrics specializes in creating facial animation for films, video games and television using a Markerless motion capture computer animation process.The Image Metrics proprietary facial animation system is a Markerless motion capture method in which an actor's performance is filmed and a 3D animated model is generated directly from the raw images.All detail seen in the recorded video is then analyzed and mapped onto a computer-generated 3D model, including the detailed movements of teeth, tongue, lips and eyes.The Image Metrics animation process captures facial details like eye movement, lip and tongue synching, subtle expressions and skin textures that can be compromised in the use of traditional motion capture methods. Advanced mapping technology allows Image Metrics to deliver facial animation results up to five times faster than motion capture methods and ten times faster than key frame animation (although this figure is subjective, since Keyframe Animation can be used to produce very different results.)

Music supervisor Ivan Pavlovich said "[we had] to pick the songs that make New York today what it is, but make sure they won't feel dated by the time the game comes out." The developers contacted over 2,000 people in order to obtain recording and publishing rights. They even hired a private investigator to locate the relatives of late Skatt Bros. member Sean Delaney to license the band's song, "Walk the Night". Citing sources close to the deals, Billboard reported that Rockstar paid as much as $5,000 per composition and another $5,000 per master recording per track.