For certain socio-demographic characteristics, rates of foreign workers whose jobs are in direct contact with clients are lower than rates for workers born to parents from France. This study looks at the reasons behind this underrepresentation. Four explanations are considered: (i) these people do not have the required skills to hold positions that require a good knowledge of the French language; (ii) they do not want to hold these jobs involving a direct relationship with clients; (iii) they work in sectors where there are generally few jobs requiring contact with the public; (iv) they are discriminated against for this type of job. In this fourth instance, the discrimination is not necessarily that felt by the employer. He may be keeping within the limits of what he believes to be the ethnic prejudices of his clientele. These different explanations were tested indirectly. A poor knowledge of the French language can probably account for a large proportion of the underrepresentation of first-generation immigrants. However, if this were the only reason, then this underrepresentation would be seen in the private sector as well as in the public sector, it would lessen the longer the person had been in France and would disappear altogether with the second generation. In fact, it occurs only in the private sector, it is similar for people who have arrived recently and those who arrived less recently and it is still present to some extent in the second generation. Nor do the differences seem to be attributable to any reluctance on the part of the people concerned for this type of profession since they often choose this type of job when they are freelance. Finally, this underrepresentation remains even after a detailed monitoring of this group of professions. The hypothesis of a specific discrimination regarding this type of job can therefore not be dismissed, even though it concerns mainly first-generation immigrants and seems to decrease over time.