The physical conditions which accompany a delta city region like the Randstad have been used to develop a strong and multifaceted complex of logistics centres. This chapter focuses on the several largest cities in the sectors of culture, conventions and knowledge. It presents a range of prime examples of interaction environments in the Randstad, leaving out interaction environments related to trade and logistics. The chapter discusses some main challenges regarding interaction environments and their integration in the urban fabric. An interaction environment is to be understood as a spatial environment with facilities for personal encounters and for the exchange of persons, goods, capital and/or information. Urban interaction environments are characterized by their combination of public spaces and buildings, which are owned and managed by multiple persons, organizations or institutions. In the interaction environments of the Holland Cluster, the term ‘park’ is to be found with various meanings.