C. Waelkens 1
1 Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200B, B-3000 Leuven, BelgiumThe accurate flux calibration of SWS requires the observation of spectra of stellar templates. On the other hand, our knowledge of stellar spectra in the broad spectral domain that ISO has opened for the first time is still incomplete, and must be improved with these same ISO data. Clearly, the final flux calibration of SWS data will result from an interactive process, that should benefit to both our understanding of the instrument and of the atmospheres of cool stars. We report on the progress of a project which confronts SWS observations of cool stars with state-of-the-art synthetic spectra.