Abstract
The process of labour market segmentation is analysed through two empirical studies carried out in the informal and modern sectors of clothing, woodworking and automobile repair in Cameroon and Ivory Coast. It appears that there exists crosscheckings at the urban incomes level. Income differentials depend on the activity as well as on the manner of employment. On the other hand, labour mobility of individuals is a rather complex phenomenon which should be envisaged in a linear perspective, i.e from the informal sector towards the modern sector. Some findings tend to invalidate certain hypotheses of probability-oriented migration models.