According to the Budget Approach proposed by the German Advisory Council on Global Change (WBGU), allocating CO2 emission rights to countries on an equal per-capita basis would provide an ethically justified response to global climate change. In this paper, we will highlight four normative issues which beset the WBGU’s Budget Approach: (1) the approach’s core principle of distributive justice, the principle of equality, and its associated policy of emissions egalitarianism are much more complex than it initially appears; (2) the “official” rationale for determining the size of the budget should be modified in order to avoid implausible normative assumptions about the imposition of permissible intergenerational risks; (3) the approach heavily relies on trade-offs between justice and feasibility which should be stated more explicitly; and (4) part of the approach’s ethical appeal depends on policy instruments which are “detachable” from the approach’s core principle of distributive justice.