The growing phenomenon of urbanization in developing countries has led to a large number of settlements characterized by a deficient habitat (slums), lacking security of tenure and an adequate provision of urban services that affect the quality of the lives of its citizens.Over time, these settlements are improving their standards of quality in the provision of public services and their security of tenure.The interrelationship between security of tenure, improved urban services and housing improvement provides the key to evaluating the actions that improve the quality of life of its inhabitants.The proposed approach involves the establishment of a methodology for reading the evolution of the forms of urban growth in terms of incremental levels of security of tenure (P), urban services (U), and building (E).In order to develop the analysis, an urban periphery index has been developed, based on the forms of evolutionary growth, improved services and security tenure, as well as on accessibility (distance to the centre and slope).The analysis of the correlation between the urban periphery index and the spatial distribution of social strata and land values, in the evolution of the urbanization of the city of Cucuta (Colombia), highlights the relevance of the elements of the urban periphery index as key factors to improve the quality of life..