The literature on international environmental agreements has recognized the role transfers play in encouraging participation in international environmental agreements. However, the results achieved so far are overly specific. Therefore, we develop a more general framework that enables us to study the role of transfers in a systematic way. We propose transfers using both internal and external financial resources for making "welfare optimal agreements" self-enforcing. To illustrate the relevance of our transfer scheme, we use a stylized integrated assessment simulation model of climate change to show how appropriate transfers may induce almost all countries into signing a self-enforcing climate treaty.