text: 27. Firstly, firm policies designed to slow city growth can emerge when current trends in migration and urban concentration threaten national development goals. Secondly, direct prohibi­ tion of migration is not necessary to slow metropolitan popula­ tion grov1th, as well aE infringing on basic individual freedoms. It is much more efficient to oblige urban dwellers to bear the full cost of urban amenities, and to avoiding subsidization of food ~rices. Thirdly, the most effective policies are those which co-ordinate administrative and economic measures both at the urban dest i.nation and the rural source. 28. In the light of these conclusions, the following measures may be suggested to deal with problems of maldistribution of population in ECA member States: the establ. ishment and strengthening of a network of small and medium-sized cities to offer a choice between metropolitan and rural life and to furnish a means of providing rural areas with much-neede~ ac~ess to a wide variety of faciities and employment opportunities: greater emphasis on regional development planning to ensure a more equi­ table distribution of employment opportunities and social amenities in different reg ions of the country; significant reforms in the machinery of development planning, as well as in the orientation of planners nd pol icy-makers; and the paying of greater attention to the organizational framework within which the various institutions and agencies involved in the development of the disadvantaged regions normally operate. 29. In particular, the development of "growth poles" in. African countries is predicated on the idea that growth in large metropolitan regions has been excessive and should be modified 136 E/ECA/Ct-1.9/5 through public intervention. Cities of intermediate size are large enough to generate significant economies of sc<le but not so large that these advantages are outweighed by conconitant dis­ economies. Net positive externalities are also greater in inter­
analysis: The text appears to be discussing urban planning and population distribution, with a focus on the economic and social implications of large metropolitan areas. It suggests measures to slow city growth, redistribute population, and promote regional development. The language used is technical and policy-oriented, suggesting a focus on economic development and planning.