Fig. 3. Network of interaction between researchers and policy makers participating in the bridging organization (Decision Center for a Desert City [DCDC]). Researchers are represented by squares and policy makers by circles. The size of the node indicates its relative betweenness-centrality (a formal network measure), which in turn is an indication of how well this actor connects other actors in the network. Actors with a high betweenness-centrality can be said to play a potentially important role as liaisons and brokers in a network of collaborating stakeholders.