Records of the 1965 International Symposium on Color Centers in Alkali Halides, sponsored by the Physics Department, Advanced Research Projects Agency, National Science Foundation, Atomic Energy Commission and Harshaw Chemical Company, including the printed program showing scheduled papers, abstracts of each paper with references to authors and related literature and indexes to authors and topics; tape recordings of review papers on optical transitions in electron-excess centers (Beall Fowler), calculation of electronic structure of lattice defects in ionic crystals (R. F. Wood), creation of defects by ionizing radiation (James Crawford), F-aggregate centers in alkali halide crystals (Herbert Rabin), influence of host lattice on color centers (Franco Bassani), anionic impurities in alkali halide crystals (J. Rolfe), rare earth impurities (Walter Bron), production of ultrapure alkali halides (C. T. Butler), trapped hole centers (Charles Delbecq), color centers in alkaline earth fluorides (A. Smakula), color centers in magnesium oxide (John Wertz) and the influence of external perturbations on optical transitions in electron excess centers (Charles Slichter) a summary paper (H. Pick) and the banquet address (R. Hilsch) and copies of slides shown with the review papers.