Model atmospheres of early type stars

We present recent progress in model atmospheres for hot stars. A new generation of NLTE wind blanketed models, together with ground-based and ISO-SWS spectra of hot stars will allow reliable metal abundance determinations (Fe, Si, Mg, Na, etc) of these objects. After checking the consistency of these results with those obtained from optical studies, we may confidently use IR-spectra of highly extinguish objects to derive their model model parameters and metal content..