  We describe a new method for the computation of opacity distribution
functions (ODFs) useful to calculate one-dimensional model atmospheres in local
thermal equilibrium (LTE). The new method is fast enough to be applied on
current workstations and allows the computation of model atmospheres which
deviate significantly from (scaled) solar chemical composition. It has
reproduced existing ODFs and model atmospheres for solar abundances. Depending
on the type of chemical peculiarity the ``individual'' model atmosphere may
have a structure and surface fluxes similar to atmospheres based on (scaled)
solar abundances or deviate in a way that cannot be reproduced by any of the
conventional models. Examples are given to illustrate this behavior. The
availability of models with ``individualized'' abundances is crucial for
abundance analyses and Doppler imaging of extreme CP stars.
