As of the 1970s, fatherhood has become a central feature of a range of legal and social policy debates in Europe. Social changes as diverse as the decline of marriage, rapidly developing reproductive techniques and women’s greater participation in paid employment have all, in different ways, posed questions about the legal rights and responsibilities of fathers. In a world that offers radical possibilities for the fragmentation of the traditional father figure, who and by virtue of what kind of links should be regarded as the legal father of a child? Is the biological connection the most decisive factor? Do marital ties existing between the biological parents preserve a mediating role in defining the father–child relationship? Should fatherhood be understood in the sense of actually doing the fathering and, therefore, require the existence of social bonds? Or, should mere parenting intentions – although not yet substantiated by social fatherhood – be considered sufficient?