At the United Nations climate change conference in 2011, parties decided to launch the “Durban Platform” to work towards a new long-term climate agreement. The decision was notable for the absence of any reference to “equity,” a prominent principle in all previous major climate agreements. Wealthy countries resisted the inclusion of equity on the grounds that the term had become too closely yoked to developing countries' favored conception of equity. This conception, according to wealthy countries, exempts developing countries from making commitments that are stringent enough for the collective effort needed to avoid dangerous climate change. In circumstances where even mentioning the term equity has become problematic, a critical question is whether the possibility for a fair agreement is being squeezed out of negotiations. To address this question we set out a conceptual framework for normative theorizing about fairness in international negotiations, accompanied by a set of minimal standards of fairness and plausible feasibility constraints for sharing the global climate change mitigation effort. We argue that a fair and feasible agreement may be reached by (1) reforming the current binary approach to differentiating developed and developing country groups, in tandem with (2) introducing a more principled approach to differentiating the mitigation commitments of individual countries. These two priorities may provide the basis for a principled bargain between developed and developing countries that safeguards the opportunity to avoid dangerous climate change without sacrificing widely acceptable conceptions of equity.