Sustainability ofcollaboration in a business ecosystem is a significant concern for organizations to survive in anincreasingly competitive marketplace. This study addressesthis concern contributing with a performance assessment and influence mechanism to measure the performance and induce more sustainable collaboration behaviours in a Collaborative Business Ecosystem. The level of collaboration can be measuredif the ecosystem's manager adopts appropriate performance indicators that, at the same time, can help influencingthe behaviour of the organisations as they try to improve their position according to the assessment metrics. A simulation model is designed to evaluate the proposed approach,and a simulation scenario discussed,showing some of the achieved results.