Why do some foreign nationalities seem to have entrepreneurial initiatives and others don't? Why do certain foreign communities tend to build an ethnic economy, and others melt in the economy of the reception country? The analysis made so far of the modes of incorporation of the different Chinese immigrant communities in Portugal allowed to evidence that, unlike what some authors defend, it is not only the cultural factors that channel immigrants into certain segments of the labour market. Several structural factors associated to these immigrants' arrival should be considered: the immigration policy of the host society; the reasons that generated the migratory flow; the existence of a co-ethnic community in the country and its economic incorporation; the operation of social networks; the possibility to acquire capital among the community (informal resources); and the potential market of the host society. Furthermore, in Portugal, as in Southern Europe, the informal economy can be an opportunity to self-employment - not so easy in North European countries where institutional control is stronger and competition is higher.