What have scholars learned over the past decade about the forces that shape the creation, design and adaptation of these institutions and their influence on state behavior? Context characteristics - knowledge; the bahaviors involved; and the availibility of alternative behaviors - can shape these factors. The strategies states, institutions and NGOs deploy, in turn, can promote insitutional formation despite Challenges or inhibit it despite propitous conditions. These context characteristics can also pose obstacles to Institutional effectiveness. Institutions prove more effective when their design reflect political and economic constrains as well as major actors' power and incentives.