  State-of-the-art NLTE model-atmosphere codes have arrived at a high level of
numerical sophistication and are now useful tools to analyze high-quality
spectra from the infrared to the X-ray wavelength range. The capacity of
current computers permit calculations which include line spectra from all
elements from hydrogen up to the iron group. The lack of reliable atomic data
has become a critical problem for further progress.
  We summarize available sources of atomic data, and discuss how these are
implemented in the Tuebingen Model-Atmosphere Package TMAP. We describe our
Iron Opacity Interface IrOnIc which is used to calculate opacities of
iron-group elements from Kurucz's and the Opacity Project's data.
  We propose general use of the Tuebingen Model-Atom Database TMAD, which would
allow an easy exchange of ready-to-use model atoms between all model-atmosphere
groups. The comparison of model-atmosphere calculations would then be much
easier, and would save a great deal of manpower that is presently consumed
preparing suitable model atoms for spectral analyses.
