University-business cooperation is important to strengthen the innovative capacity of the economy. Until recently, universities where rather hesitant to engage with local business but with recent changes in the higher education landscape, universities have started to become more "entrepreneurial." Therefore, little is yet known about critical success factors for the establishment of these new ties and cultures of cooperation. For the purpose of this study, one German university who strives to become more entrepreneurial by working more closely with local business was chosen as a case study. We analyzed the main factors for a sustainable cooperation in an established network for innovation and transfer as a concrete example of university-business cooperation. Using a mixed-methodology approach a quantitative survey of the participating partners as well as qualitative case studies was conducted to measure the success of this cooperation through knowledge transfer and to gain insights in the success factors. We identified three relevant factors: knowledge management, cultural integration, and relationship management. Personal attributes of network members emerged as another important factor as a kind of precondition to engage in university-business cooperation.