Romanian soldiers participate in counter improvised explosive device training with Canadian Forces instructors during exercise Rapid Trident 2013 in Yavoriv, Ukraine, July 12, 2013. Rapid Trident is an annual joint combined exercise involving the U.S. and Partnership for Peace member nations. Missions alternate in odd and even years. In odd years Rapid Trident is a field exercise, while in even years the exercise incorporates a command post exercise.