This work aims to put into perspective the mechanisms of the fight against social vulnerability in urban and peri-urban areas. The general objective of this study is to show how development projects take place in the fight against vulnerability through the dynamics of interaction networks, which strengthen the production capacities and skills of the actors concerned. In fact, the author shows in this research, an economic sociology turned towards the daily life of actors who seem to be forgotten by the public authorities. Under the threat of death, they undertake viable socioeconomic projects that are sometimes not stable in order to respond spontaneously to the basic social needs of the associated members for the collective interest and sometimes for the individual interest. In fine, we can say that the activities carried out by these people in the city of Douala in Cameroon are part of a dynamic of exchange to support the employability of the population that is struggling with the employment crisis and is sometimes forgotten by the public authorities.