The integration process can have a significant effect on the performance of MutiAgent systems (MAS). At present, most of the integration approaches of MAS focus on the behaviour and performance at the system level. In this paper, we are concerned about the performance of multiagent systems as well as the revenues of individual agents. This paper presents an approach to the integration of multiagent systems based on twoway selections. In the approach, agents apply for the roles accroding to their capabilities and how well the  roles meet their desires, while the  roles choose agents based on how well the agents fulfill tasks. In the process of twoway selections, the roles will evaluate the degree of trustworthiness of the agents dynamically and adjust the trust degrees in time. Experiments show the performance of multiagent systems can improve rapidly and the revenues of agents can gradually increase in a given interval.