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The role of hydroxide and peroxide impurities on color-center properties in sodium fluoride were studied with several crystals grown with the Kyropoulous technique. The optical absorption in peroxide doped samples consists primarily of three bands at 275 millimicrons, 235 millimicrons and 195 millimicrons respectively. The production of F centers is determined almost entirely by impurities with a small contribution due to intrinsic processes. The large coloration in hydroxide and peroxide doped samples are explained on the basis of photochemical reactions involving impurities which act as sources of anion vacancies and electrons. Important differences were observed in hydroxide and peroxide doped samples in relation to the charge state of the aggregate centers. Electron-deficient centers are stabilized and the probability of their formation is enhanced in hydroxide doped samples. In peroxide doped samples the excess electron centers are favored. Several new absorption bands were observed in hydroxide and peroxide doped samples.