Convergence in life sciences is an ongoing evolutionary process that has been highlighted in numerous official documents in the context of the Review Conferences or the Meetings of the States Parties to the Biological Weapons Convention (BWC). A special place in these discussions is devoted to the advancements in the synthesis of such components, like bioregulators or toxins facilitated by the developments in biotechnology, chemistry, and other disciplines. Given the expected instrumental changes within the BWC (the possibility of a verification mechanism, an S&T Advisory Board) it is worth discussing the challenges that both the Chemical Weapons Convention (CWC) and the BWC could face in dealing with the conversion in S&T, in particular in the areas where the provisions of both Conventions overlap (as in the case of toxins and bioregulators). This might pose challenges when the BWC successfully develops a verification mechanism.