The document discusses similarities and differences between four pharmaceutical clusters: Pill Hill Mississauga, East England, Cork City Ireland, and an unnamed fourth cluster. It provides examples of shared cluster members like AstraZeneca being present in multiple locations. It also describes various marketing and support structures within the clusters, such as educational programs, research centers, incubators, and conferences sponsored by government agencies and cluster members. Strategic partnerships and alliances between members are highlighted as ways to stimulate innovation within the clusters.