We present a system based on commodity graphics hardware for computing global illumination in dynamic scenes at interactive rates. We designed a progressive global illumination algorithm specifically to take advantage of current graphics hardware features. Our algorithm simulates the transport of light in synthetic environments by following the light emitted from the light source(s) through its multiple bounces on the surfaces of the scene. The entire algorithm runs on ATI?s Radeon 9700 using vertex and fragment shaders, allowing us to compute and display a global illumination solution for reasonably complex scenes with moving objects and moving lights in approximately 250 milliseconds (4 frames per second).