Partnerships are now essential to public service delivery. However, due to limitations in collaborative capacity, there are both obstacles and motivators for forming partnerships. Intergovernmental and cross-sectoral partnerships offer different advantages and disadvantages in extending public service missions in new directions. Using survey data of local air quality agencies, findings determine different factors contribute to partnership and non-partnership. Further findings suggest partnerships are driven largely by problem severity, but non-partnership is driven by specific benefits and risks associated with types of partners. Conclusions indicate that understanding non-partnership is a key to understanding partnership formation.