Modern multi-organisational coalitions are capable of bringing diverse sets of capabilities, assets and information sources to bear on complex and dynamic operations. However, the successful completion of these operations places demands on the trust between coalition partners. When it is necessary to rely on other partners, decision-makers must be able to make rapid and effective trust assessments and decisions. In this paper, we introduce computational trust mechanisms, and illustrate how they may be employed in coalition information acquisition. We discuss how these mechanisms can draw on different sources of evidence to make assessments of trust, and arrive at decisions about how to act when trust can be supplemented by controls. Finally, we discuss future directions for these systems, and highlight some challenges that remain.