The various contributions to this theme issue are likely to have at least two (non-trivial) things in common. First, they aim to contribute to a research project on “Legal certainty for globalized exchange processes” and to the latter's attempts to explain the observed transformation “towards the transnationalization of commercial law, which is understood as a combination of the internationalization and privatization of the responsibility of the state for the production of the normative good of legal certainty for global commerce”. Secondly, they aim to fulfill this task by making use of “evolutionary theory” or, as it was again expressed in the original conference announcement, by dealing with “a theoretical perspective that gives some substance to the meaning of the term “evolution” with regard to law, social organization, and the state”. Since, as I will try to explain shortly, my own particular take on this – it would appear – relatively small set of commonalities involves more specifically the use of contemporary evolutionary approaches to human behavior. I must admit to having been surprised that no one else seemed to have much use for these approaches in their respective takes on the problems that united us in the conference from which this contribution stems. After all, what better use to make of a theory originating from biology than to elucidate the biological underpinnings of our behavior and its underlying psychological mechanisms as they relate to law and legally relevant phenomena? Perhaps some of the reasons for these at first sight, striking differences in opinion on which “evolutionary theory” to make use of, or what meaning to impinge upon the term “evolution” will become clearer in the pages that follow, offering ways in which eventually to combine them. Or perhaps the two things we had in common when we started out will be all there is left to look at in the end.