The success of virtual communities (VCs) relies on collaboration and resource sharing principles, making trust a priority for each member. The work presented in this paper addresses the problem of trust management in open and decentralised virtual communities. We address this problem by proposing an Adaptive and Socially-Compliant Trust Management System (ASC-TMS) adopting a multi-agent based approach. Our proposal relies on the joint use of trust policies and meta-policies, which allow VC members to exhibit adaptive (i.e., in accordance with environment changes) and socially-compliant (i.e., in accordance with the collective policies specified by the community members) behaviour. The experiments reported in this paper focus on the socially-compliant aspect of ASC-TMS. They aim at evaluating different policy integration algorithms.