The seeds of war are often sown during war. Violence associated with armed conflict adds more grievances to those that led to conflict in the first place. Of the 259 armed conflicts identified by the Uppsala Conflict Data Program (UCDP), 159 recurred and 100 involved a new group or incompatibility. 135 different countries have experienced conflict recurrence, and the pattern is deepening. Recurring conflict is symptomatic of unaddressed grievances, and lasting peace will not be achieved until these issues are addressed. Peace agreements guaranteed by peacekeepers are much more likely to prevent wars from recurring in the years immediately following war. In the long-run, political reforms are necessary to ensure durable peace.