The new models incorporate a large part of the now extensive knowledge of continuous and line opacities of atoms and di- and polyatomic molecules. Edvardsson et al. (1993) demonstrated the large impact of the extensive theoretical metal line absorption data calculated by R. Kurucz (Cambridge, MA) on model atmospheres for solar-type stars. For cooler stars the impact of molecular lines are considerable, and new data for several important molecules have been produced and compiled for the project. The warmer models will be extensively used in the other projects described here, and a large grid of model atmospheres will be made available to all astronomers.