The impacts of climate change — drought, rising sea levels, melting glaciers, extreme weather — threaten to further destabilize already fragile states. To address the resulting security risks, EU and U.S. decision makers should build a strategic partnership that involves the foreign and security policy communities as well as the development community. The appropriate response to the risks of climate change will not be limited to one country or to the military domain; rather, it must be both multilateral and multi-faceted, encompassing the full range of available policies including development cooperation, conflict prevention, and humanitarian assistance, as well as climate change adaptation and mitigation. The development of adaptation strategies, efforts to reduce deforestation, and the preparation of low-carbon development strategies all offer promising ways to help reduce the security threats of climate change. By designing these instruments in a conflict-sensitive way, the transatlantic partners can help bring climate change concerns into mainstream development, foreign, and security practices.