A quarter of the world’s population (and half its urban population) lives in urban centres with fewer than half a million inhabitants. Of the 1.5 billion people living in these ‘small urban centres’, nearly three-quarters live in Africa, Asia and Latin America. Several hundred million more live in these same regions in ‘large villages’ that have urban characteristics and that could be classified as urban centres. These ‘small urban centres’ and ‘large villages’ are also likely to absorb a large part of the growth in the world’s population up to 2025 and beyond. This paper draws on recent census data for some 70 nations in Africa, Asia and Latin America to examine the proportion of national populations living in ‘large villages’ and in urban centres in different population-size categories. This highlights their demographic importance in virtually all nations. Such urban centres also have considerable economic, social or political importance within almost all nations; in many nations, they contain a sizeable part of all economic activities and include almost all the service centres and local government centres for rural populations and for agriculture. Most small urban centres exhibit a mix of urban and rural characteristics. However, most rural specialists choose not to recognize the importance of small urban centres within ‘rural development’, and most urban specialists fail to recognize the importance of prosperous agriculture and a prosperous agricultural population for urban development. Recognition of the demographic, economic, social and political importance of small urban centres might help to shift such biases.