In the Netherlands, policy attention has shifted recently from the territorial scale of the Randstad Holland to the North Wing (Amsterdam) and the South Wing (Rotterdam-The Hague) when it comes to fostering integration and hence metropolisation. This chapter describes the process of integration in the Metropoolregio Rotterdam The Hague in the southern part of the Randstad. From 2010 onwards, the formation of the Metropoolregio Rotterdam The Hague has taken off in a fast pace, triggered by a political discussion about the abolishment of the Dutch city-regions. Moreover, there is a strong economic incentive to join forces at the metropolitan scale in order to improve the (inter)national connectivity of the region as well as to enhance the region’s competitiveness. This chapter discusses how the twin-cities Rotterdam and The Hague are becoming more and more dependent on each other, boosted by a process of functional, cultural and institutional integration.@en