Since its creation in France in 1999, the civil partnership (Pacte civil de solidarité, or PACS), which provides recognition for same-sex couples in terms other than those of marriage, has become increasingly popular among heterosexual couples. While contemporary transformations in types of union and in sexuality are often studied independently, this article breaks with this dissociation to challenge the hypothesis whereby individuals who register a PACS in France present attitudes and behaviours with respect to sexuality that reflect the normative diversification observed by the group "Context of Sexuality in France" (Contexte de la sexualité en France, CSF). Using data from the CSF survey of 12,364 individuals conducted by INED and INSERM in 2005-2006, we studied the relationship of individuals in PACS unions with the three main components of the dominant normative order in sexuality: heterosexuality, interlinking of conjugality and sexuality, and the value placed on "alternative" practices. PACS unions are compared with other types of union. We find that persons who opt for the new type of registered partnership have specific characteristics that relate more to liberal representations of sexuality than to actual differences in practice. Behind this specificity lies a considerable gap between the sexes, even though differences between men and women in PACS unions are sometimes relatively smaller.