  We develop an extension of the well-known BCS-theory to systems with trapped
fermions. The theory fully includes the quantized energy levels in the trap.
The key ingredient is to model the attractive interaction between two atoms by
a pseudo-potential which leads to a well defined scattering problem and
consequently a BCS-theory free of divergences. We present numerical results for
the BCS critical temperature and the temperature dependence of the gap. They
are used as a test of existing semi-classical approximations.
