MIGRATION CON T Many city administrations in the Third World have sought to limit rural-urban migration an ven to reverse the ow employing a series of sures including administrative and legal controls on population moveme police registration schemes and direct rustication programmes to relocate urban dwellers in the countryside. These strategies have had most success in socialist states. In China, in order to slow the rate of urban- sation and reduce emerging income and welfare differentials between urban and rural areas, the government in 1958 introduced a population regis tration system, (hukou), that classified people as either urban or rural residents. Limiting the number of citizens who could be registered as urban dwell- ers restricted the numbers moving cities to opportunistically in the hope of finding work. The registration scheme was supported by rationing of food, which was available in cities only to those in possession of an urban household registration document. In the absence of a significant black market these measures proved highly effective in slowing the rate of rural emigration albeit at a cost to personal liberty. Migration controls were complemented by rustication programmes that resulted in the movement of 30 million urban resi- dents (including 17 million young into the people) countryside during the period 1966-76.2 These measures continued until the late 1970s, when the policy was relaxed to support China's industrialisation