One light-polymerized, three heat-polymerized, and three autopolymerized denture base polymers were exposed to coffee, tea, water at 50 degrees C +/- 1 degree C, as well as artificial sunlight and water, and evaluated for color stability. The color characteristics were determined using a computer-controlled spectrophotometer. Water sorption and solubility were assessed, and the materials were also chemically characterized. Coffee and tea stained the denture base materials superficially. Brushing with toothpaste and moderate grinding reduced discoloration to an acceptable level. All materials were relatively color stable when immersed in water at 50 degrees C +/- 1 degree C. The materials behaved differently when exposed to artificial sunlight and water.