States parties to the Chemical Weapons Convention (CWC) will convene for the Third Review Conference of the treaty in April 2013. With the destruction of chemical weapon stockpiles more than 75 per cent complete and ongoing changes in the scientific, industrial and security environment in which the CWC operates, some have argued that major adaptations in the implementation of the treaty are required. However, on the basis of regular participant observation at CWC meetings of states parties and extensive document analysis this article argues that changes in treaty implementation will be only of an incremental nature with the Organization for the Prohibition of Chemical Weapons (OPCW) taking on new tasks in the areas of chemical terrorism and safety and security, alongside traditional core areas of activity in CWC implementation such as verification of chemical weapon disarmament, non-proliferation or, rather, non-acquisition of chemical weapons, protection and assistance against the threat or use of chemical weapons, and international cooperation in the peaceful uses of chemistry. Taking into account the evolution of these areas of concern in combination with the consensus-based institutional culture of the OPCW supports the expectation of only incremental changes being adopted at the Third CWC Review Conference. These expectations tie in with the findings of organizational analyses in other political contexts, which highlight the path dependency of many institutions once they are created.