The purpose of this paper is to investigate the effect of privatization in a mixed duopoly, where a private firm competes in quantities with a welfare-maximizing public firm. We consider two inefficiencies of the public sector: a possible cost inefficiency, and an alloca-tive inefficiency due to the distortionary effect of taxation (shadow cost of public funds). Furthermore, we analyze the effect of privatization on the timing of competition by endog-enizing the determination of simultaneous (Nash-Cournot) versus sequential (Stackelberg) games using the model developed by Hamilton and Slutsky (1990). The latter is especially relevant for the analysis of privatization, given that results and policy prescription emerged in the literature cruc...