Radiative Corrections to Supersymmetric Higgs Boson Masses

We discuss the large radiative corrections to the masses of supersymmetric Higgs bosons in the MSSM and in its simplest extension, the NMSSM, with particular attention paid to the bounds on the lightest CP-even Higgs mass found in both models. In the case of the MSSM, these corrections are found to be primarily associated with the effects top quark and stop squark loops, while for extended models they also include significant contributions from Higgs and Higgsino loops.