A study is described that investigated the influence of a target group's communication network on information diffusion and the impact of a community-based information program. It was expected that the process of information diffusion would be related to the quantity of ties. The diffusion of information brought into a clique by external sources that did not belong to any of the target group's cliques was expected to be related to the existing number of weak ties, whereas the diffusion of specific information sent out by internal sources within a clique was expected to be primarily related to the number of strong ties. Furthermore it was expected that the impact of the program would be related to the perceived quality of network ties. Results support the hypotheses and confirm Granovetter's “strength-of-weak-ties” hypothesis. In addition, existing direct ties between the internal sources of information and the target group appeared to have played a crucial role in the process of information diffusion.