We investigate an innovative sol-gel method that allows coating of mineral or plastic substrates with colloidal oxide-based materials and/or inorganic-organic composites and/or hybrids. To date, we have developed narrow and broadband antireflective coatings, multilayered dielectric mirrors, and a few polarizing thin films. These sol-gel optical coatings have demonstrated adequate performance for use in our proposed 2MJ/600TW (351 nm_ Nd:glass laser. To prepare such optical thin films, sol-gel technology offers outstanding technical and economic advantages over physical vapor deposition. Sol-gel technology opens new prospects in a variety of coating applications, and few areas offer greater payoff for interaction across disciplines than that of sol-gel-derived thin films.