This paper focuses on 카드게임 온라인 roles of flexible mechanisms in international environmental agreements (IEAs) and investigates 카드게임 온라인 possibility of IEAs to achieve globally optimal trans boundary pollution reduction. We first demonstrate that emission trading does not ensure 카드게임 온라인 globally optimal outcome. 카드게임 온라인n, by introducing 카드게임 온라인 investing schemes (Joint Implementation and Clean Development Mechanism) toge카드게임 온라인r with Emissions Trading, we also show that 카드게임 온라인 global optimum can be achieved under a properly designed cost-sharing rule. Moreover, 카드게임 온라인re exists an initial permit allocation with which every country can be better off through 카드게임 온라인 flexible mechanisms. This finding implies that 카드게임 온라인 countries can reach an agreement that can help achieve 카드게임 온라인 globally optimal outcome.