Emissions trading schemes (ETSs) have emerged as stable components of a fragmented climate governance landscape. Yet the proliferation of ETSs raises critical questions concerning their design, the development of conflicting norms, and how such schemes might link. This Article engages with these concerns by advancing a linkage framework based on a series of core convergence criteria which are considered necessary to assess the compatibility of candidate partner schemes. For the EU, the search for a candidate linkage partner has seemed a Sisyphean undertaking, but it is suggested that South Korea offers the prospect of stable climate settings. The critical design features of South Korea’s Emissions Trading Scheme (KETS) are evaluated before applying core convergence criteria to evaluate compatibility. This Article identifies a degree of alignment between the design features of the EU’s flagship Emissions Trading Scheme (EU ETS) and the KETS, but also uncovers divergences where detailed negotiation will prove necessary.