If we further study the migration issue with the migrants being the labour force of an African city nowadays, then when we talk about migration, the repulsion and the attraction issues come up at the same time. The cities are attractive, but because of the rural areas, people feel forced to migrate to cities. Why? Because most of the rural areas cannot meet the needs of the entire population. Conversely, there is also a strong attraction to the city, where it feels, often rightly, that it is easier to find a job. So it is a game between being attracted by the city and being pushed out of the rural areas. It is absolutely clear that one of the main reasons for migration is to find better living conditions, a job more easily and the concentration of people, as they are the driving forces of urbanisation. Precisely, one of the main features is that the network is larger, the networks are numerous and the job opportunities will increase in the city compared to the countryside. Next comes the informality issue. It is one of the features of the African cities. It means that in most cities, a part of the economy, if not all, happens through an informal channel, out of the regulations, out of the laws, meant to formalise all the activities. So by dint of informalities, the border between formal and informal narrows and we are not sure if we are in the formal or informal anymore. It also means that in African cities, the informal becomes the rule. So the question here is: should we continue to act as it has been until now, trying to formalise the informal, or should we use the informal as a new paradigm, and to rebuild an urban management to plan on existing mecanisms There are two main groups of actors: the institutional actors and the private sector. Within the institutional actors there will be the national level with the ministries and the organisations under supervision, and the local level with municipalities or local councils. Within the private sector, there is the formal or associative sector: companies, NGOs, development partners and the informal sector issue: the community of poor people, the ordinary people, the people living in the cities. Some can be active on the informal level, trying to be organised, but always in an informal way. This is roughly what the actors do. There can be additional layers, some relations can be very close between development partners and organisations under supervision. So between the private sector and the institutional actors, but it is the basic pattern of the actors in development. The issue of urban macrocephaly is the basic pattern we have. In general, there is one big city per country. It is the case in Dakar, Conakry or Nouakchott, or Tunis as well, where the majority of urban people live in this big city. There is also a bicephalic phenomenon, so we drift apart from the macrocephaly. For example in Douala-Yaoundé. Or, we have networks of cities like in South Africa, in Nigeria. Or booming of a region or urban continuum, for example in Nigeria, but also in the whole region between Lagos and Cotonou. So the basic pattern stating a macrocephaly does exist in many countries, it exists in Bamako, Mali, however, the number of exceptions is so high that we cannot make a generalisation for urban macrocephaly. Finally, talking about characteristics, we must talk about the colonial heritage. All African cities are not colonial cities, but most of the cities we discuss today, the big capitals have a colonial past. A colonial city is a dual city, between the city centre and outlying districts, between the administrative centre for elites and outlying districts, mostly for working class people. Currently, we see that the first sketches of the colonial city still have an influence today on future plans. The features of the colonial city were actually quite simple. There was a strict zoning between working class and indigenous areas and the city centre reserved to the elites. The state had control over real estate. Most of the lands belong to the state. Then would come the housing scheme, the favourite tool in urbanism as we would proceed in the same way, one residential area after another. Today, the same process applies despite the planning guidelines and all strategy plans for development. We must admit that the African city, as we will see on week eight, grows through its housing schemes. So the challenge is peripheral, and it also depends on the competence of the city planners to create spatiality in the housing schemes, since the key for tomorrow's city lays in the outskirts, in the future residential areas. To conclude this overview of the African cities and what characterises them, let's talk about the "urban crisis". The urban crisis is a rupture in a certain number of regulations. First, the spatial burst. The city's surface grows much faster than its population. Even if the population growth is sustained, the spatial burst, the area covered by the city is much bigger and there is a disconnection between space and the number of people. There is a financial crisis in countries undertaking structural adjustments. That was a requirement from the World Bank back then. So there is an obvious incidence in the spatiality of the cities. There is also a real estate crisis, between modern management and more traditional management. Finally, the state has taken some land back in the formality process, and there are the customary claims. There is a back and forth between the customary lands and the state lands. The prices collapse and a scarcity of external sources arises. So what was being sold at a high cost on the foreign market will collapse. This is the case of the Ivory Coast in the eighties. And finally the financial godsend will stop coming in and will cause the failure of many urban policies, especially housing policies where funding did not follow the implemented policy. All this adding to the infrastructure crisis, where we saw the importance of the spatial burst. There is again a disconnection between the capacity of infrastructure, to produce a network and the surface area, as well as the number of people. Eventually, all these ingredients make the recipe for disaster and the urban crisis arises. This is what we have in nearly all African cities. We have not talked about the historical question, the pre-colonial issue, of course. We cannot pretend that cities did not exist before the colonial period. What we are covering here is mainly the colonial cities, as they are the ones that will become the big capitals. It is the majority of the cities that we will study for a few weeks. But keep in mind that there was a strong urban network, especially in Nigeria, before the colonial period, and we talked about the cities in the Maghreb that have existed since Antiquity. There are multiple examples. Instead of looking at some features, we could also have considered the city with a historical vision and its evolution through time. We will also list some publications and texts in the bibliography that will help you study further, as we have very little time for the subject we are covering. This is it for African cities with these few minutes of video enabling us to have a quick overview of African cities.