chi² Analysis of Supersymmetric Models

We discuss the results of a global fit to precision data in supersymmetric models. We consider both gravity- and gauge-mediated models. As the superpartner spectrum becomes light, the global fit to the data typically results in larger values of chi^2. We indicate the regions of parameter space which are excluded by the data. We discuss the additional effect of the B(B --> X_s\gamma) measurement. Our analysis excludes chargino masses below MZ in the simplest gauge-mediated model with mu>0, with stronger constraints for larger values of tan beta.