The concept of “common but differentiated responsibilities” (CDR) is receiving increasing recognition in international law. “Common” suggests that certain risks affect and are affected by every nation on earth. These include not only the climate and the ozone shield, but all risk-related global public goods, including peace, public health, and terrorism. In reducing the mutual risks, all nations should “cooperate in a spirit of global partnership.” Responsibilities are said to be “differentiated,” however, in that not all countries should contribute equally. CDR charges some nations, ordinarily the Rich, with carrying a greater share of the burden than others, ordinarily the Poor.