##Summary In this chapter we explored models of collective action where agents make decisions of cooperation conditionally based on the decisions of their neighbors. We explore different spatial configurations and observe that the ability to select partners leads to the highest performance of the society. When groups grow over time with more altruistic agents at the start, a higher level of cooperation can be achieved.
##References Granovetter, Mark (1978). Threshold Models of Collective Behavior. American Journal of Sociology 83 (May): 1420-1443.