In large countries in the modern world, the only significant alternative to a market economy has been central planning as was practiced in the early Soviet Union and in the People's Republic of China before the 1990s. Other proposed alternatives to the market economy (participatory planning as proposed in the theory of participatory economics (parecon), an artificial market as proposed by advocates of Inclusive Democracy and the idea of substituting a gift economy for a commodity exchange) have not yet been tried on a large scale in the modern industrialized world.