This chapter describes the reasoning behind the proposed introduction of flow-based market coupling to the Nordic power system. The chapter then discusses flow-based market coupling specificities in the Nordic Capacity Calculation Region, including the use of Advanced Hybrid Coupling and the impact of power system dynamics. Moreover, this chapter shows how the combination of flow-based market coupling and the creation of the Nordic Regional Coordination Centre will result in advanced collaboration between the countries including a more coordinated and data-centred capacity calculation process. The External Parallel Run of the flow-based capacity calculation methodology, currently being performed by the Nordic Transmission System Operators, is described and the initial results are discussed. The chapter closes with a brief overview of stakeholder engagement and the next steps for implementation of flow-based market coupling.