“But in my experience, there is one way to signal your commitment to process that all negotiations provide: Always keep your word, even when it is costly. The best deal makers and diplomats take very seriously the promises and commitments they have made to the other side on small things and big. This is not only the right thing to do; it is a tremendously powerful instrument in deal making. Especially in difficult, protracted conflicts where negotiating itself might be seen as risky or useless, often the only source of leverage you have for bringing the other side to the table is your credibility. And once you’re at the table, mistrust is often the biggest barrier to the give-and-take necessary for progress, because many of the concessions either side commits to are not deliverable right away—promises of equitable treatment, power sharing, future benefits, etc. are necessarily premised on trust. If you have not built up a reputation for credibility, you are ill-suited to negotiate such deals.”