In service-oriented environments, service providers orchestrate distributed services from other providers to create new composite enterprise services. A component service can be invoked jointly by several distributed composite service providers. However, because a composite service is provided to the consumers as an integrated service, when failures or dissatisfaction of the consumers occurs, it is not possible to directly identify the untrustworthy component. In this paper, we describe a collaborative trustworthiness determination approach using optimisation that can provide a solution to selecting trustworthy component service constructs based on monitoring and consumer quality of experience reporting of existing composite services from peer providers. Copyright © 2014 John Wiley & Sons, Ltd.