Whereas small and medium enterprises can answer the different business challenges through cooperation within collaborative networked organisations (CNOs), human aspects constitute a fundamental issue in these networks since it is neither organisations nor information systems but people that cooperate. This paper addresses the major human aspect considered in vertical CNOs, namely trust that can significantly impact knowledge and know-how exchange as well as information sharing. A case study on Swiss Microtech, a vertical collaborative network from the industry of machining operations, is presented and discussed with respect to these issues. With the help of an analytic hierarchy process technique designed and developed, different trust types are identified, their corresponding weights are evaluated and their relationships with information sharing and exchange are discussed. The results show that the institutional perceptions of trust and its attributes in the enterprises studied are very close to each other. Furthermore, out of the five identified types, only competence, relational and contractual trust categories have a significant impact on strengthening the relationships between enterprises belonging to a vertical CNO.