Multi-layered Bi/Se/Bi/Se... films were prepared by thermal evaporation. Optical writing experiments on these films showed an exceptionally high sensitivity for the following reason: the absorbed light heats the film until it begins to melt, at which point an exothermic reaction between the Bi and the Se releases more energy. The bits written on the multi-layered Bi/Se films are very clean and comparable to those of the best known optical recording media. Intrin-sic S/N, corrected for the substrate defects on these films, is the same or slightly better than that of 300A pure Te thin film on glass substrate. It should also be noted that an earlier study by AT&T Bell Laboratories showed an exceptionally good environmental stability of the Bi/Se bilayers. In fact, some Bi/Se bilayer films made more than 10 years ago still show little signs of degradation. For write° pulse energies below that required to form a hole, the write beam caused the reflectivity of the film to increase. The reflectivity increase effect could be used to write format information, while hole formation could then be used to record user data. Salient features of the optical recording characteristics of these media, as well as the material preparation technique, will be presented.