Various family forms are open to different-sex and/or same-sex couples: marriage, registered partnership, formalized cohabitation, informal cohabitation. The level of legal consequences (rights and obligations) of these family forms varies greatly from country to country throughout Europe and it has substantially evolved over the past few decades. Similarly, couples vary greatly in their choices for the different family forms throughout Europe and these options have evolved though time. The latter differentials and trends are documented by statistics we have collected in a number of countries and we have compiled in a series of tables. Users are invited to analyze this dataset and look for possible links between couples’ behaviors and legal consequences attached to family forms. More generally, the dataset is open to international comparisons in order to test whether legal contexts are factors of differentiation in behaviors regarding access to marriage or registered partnership. The results of such comparisons will be a new contribution to the research on same-sex families, filling the existing gap imposed by traditional data limitations, and evaluating the implications of extending same-sex rights.