Commitment protocols formalize interactions among autonomous, heterogeneous agents, leaving the agents' local policies unspecified. This paper studies the problem of agents enacting commitment protocols, which inherently requires that their policies cohere with the given protocols. Specifically, in many important settings, if agents incautiously create and discharge commitments, they can expose themselves to certain risk; conversely, if the agents are (excessively) cautious, a protocol enactment may deadlock. This paper adopts the well-known idea of monotonic concession, but specializes and enhances it with the particular features of commitments. Specifically, this paper formulates inference rules for commitment concession that respect the nature of commitments. Next, it shows how commitments can be systematically revised as the agents incrementally engage each other in enacting their protocol. This paper demonstrates how such rules can be applied in practice, and identifies conditions under which progress and termination of protocol enactment can be guaranteed.