Mikhail S. Gorbachev has pledged himself to the lofty goal of revitalizing a society of nearly 300 million people. After a hesitant start, he has cast himself as an advocate of far-reaching reforms in the Soviet economy, in communications and culture, and, most fascinatingly, in political institutions. Gorbachev's reed-thin margin of victory in the Politburo dictated that his changes begin there. He scored a breakthrough at the April and July, 1985 plenums of the Central Committee, which ushered four new members into the Politburo. The early Gorbachev invited innovation in economic and social policy. He was also vaguely receptive to institutional change, at least in the economy. Gorbachev's Politburo has increased capital investment, given priority to non-military technological modernization, and begun to supply schools and factories with microcomputers. Planners and managers are being pressed harder to deliver goods and services to the consumer.