The term knowledge‑intensive business services (KIBS) indicates private companies whose job consists of collecting, generating, analysing, and distributing knowledge with the purpose of delivering customized services to satisfy client’s needs. KIBS firms rely on highly educated professionals, and supply knowledge resources or other knowledge‑based services that clients are unable or unwilling to develop by themselves. The provision of KIBS entails a bilateral exchange of knowledge between the service provider and the end user along with the entire supply cycle. In this process, not only KIBS firms supply clients with precious elements of technical and applicative knowledge, but also client firms provide KIBS with pieces of knowledge that are necessary for designing a successful solution. As is well underlined in the literature, trust is an essential ingredient of client‑provider knowledge exchanges, so that KIBS companies have deal with it properly. This is not simple, since trust has several dimensions that rely on different trust‑building mechanisms. In light of this, the paper aims to analyse the different forms of trust and the related trust‑building mechanisms that come into play during the delivery of a knowledge‑intensive service. This is done by discussing the findings of a multiple case‑study of a particular group of KIBS, i.e. computer service companies located in the Northeast of Italy. Specifically, the study: a) offers a knowledge‑oriented description of the interactions that take place during the service delivery process between client and KIBS firms; b) analyses the role played by the different forms of trust, as antecedents and consequences of each interaction; c) makes some remarks about the trust building mechanisms that a KIBS company can exploit, and the resulting management implications.