The first part of this article deals with the problem of fidelity to the father's party allegiance.Socialization by the parents seems to be more effective in catholic and socialist families than in liberal (= conservative) families; it may be intimitaly related to a socialization of a religious or a laicist nature.Socialization by the parents was more effective in the past; younger people show a tendency to be less influenced by it.Socialization by the parents is more effective when the ideological context tends in the same direction (catholics in Flanders, socialists in Wallonia). The second part of the article deals with the problem of voting homogeneity with couples. Results lead to the conclusion that the large uniformity of political behaviour within couples expresses two tendencies: the fact that in most cases one marries within the ideological «family». One belongs to and the fact that marriage exerts a socialization which is essentially influencing non-catholics.