This chapter aims to contribute to the evolving literature on trust processes in inter-organizational relations by introducing the concept of imprinting. Imprinting is a highly useful concept for understanding trust as a process, because imprints are conditions or perceptions that are created during short, critical periods and remain stable over time. By understanding the conditions under which such imprints will change over time, we gain insights into which perceptions of trustworthiness are stable and enduring and which perceptions are more readily prone to change. Despite the numerous studies on imprinting, it remains to be discussed further in relation to trust processes and inter-organizational relations. Insights into the imprinting process are gained from an explorative longitudinal study of two partners on a construction project that occurred in 2009–13. This chapter offers insights into how we can understand imprinting in relation to trust: specifically, how trust imprints are created, how imprints persist and why imprints change. First, it offers an understanding of how early imprints affect behaviours during uncertain periods. Secondly, it provides knowledge of how imprints remain stable and how new layers of imprints are created as partners interact with and learn about one another. Thirdly, it offers an insight into how sensitive periods, during which trust is tested, give rise to new imprints that are quite persistent over time. Fourth, it provides an understanding of how imprints can fade and resurface when new uncertainties arise. In this manner, trust draws on imprints but also creates new imprints.