We consider the most probable value of conductance of a disordered quantum conductor in the framework of the random matrix theory developed earlier. Analytic calculations are possible in the metallic as well as strongly localized regimes. We make a simple assumption on the eigenvalue density, as suggested by numerical work, and explore the consequences of a one-parameter distribution. A key result of the one-parameter scaling theory, that there is true metallic behavior only in dimensions greater than two, is recovered naturally