Ethiopia is the second most populated country in the Sub-Saharan Africa, with 85 million of inhabitants. At the same time is one of the least urbanized countries, with only the 17% of the population living in urban areas. In the last decade, however, the capital Addis Ababa has suffered a wave of urbanization without equal but the inadequacy of planning tools is getting in the way of a proper development, leading to the exasperation of social conflicts and to the exacerbation of the slums situation. This book is focused on the relationship between formal planning and informal settlements in the city of Addis Ababa, analyzing the current situation of the urban fabric, its origins and the upgrading projects so far implemented. The aim is to outline a sustainable strategy for the design of new urban scenarios, starting from the upgrading of informal settlements through the protection of the traditional ways of living and social networks of interaction.