Though the Clean Air Act (CAA) relies on a traditional inter-government partnership, new initiatives from local governments that fall outside of the conventional implementation strategy have created a unique public service delivery network by adding layers to the implementation scheme. Using both logistic and multinomial logistic models and a dataset of 497 Metropolitan (MSA) and Micropolitian (µSA) areas, this research tests a model of network membership for local governments based on internal organizational and external network factors. Findings indicate policy problems, perceptions of resource availability, network density and structure, and socio-economic and political factors affect local initiative to expand networks.