We report accurate nonrelativistic CI results for He, Li, Ne, Ca, and Ca−ground states using a new automatized code for large‐scale calculations. Salient features include efficient optimization of nonlinear one‐electron function parameters and a hierarchical strategy to approximate the full CI energy. We have also developed a variational principle for relativistic atomic states. With this principle we evaluate relativistic SCF solutions working on a precise eigenvalue (usually of very high order) of the CI Hamiltonian and implementing Brillouin’s condition through an iterative process. The same variational principle is also applied to full CI expansions, as well as to limited well‐defined CI expansions.