This thesis identifies the role of trust in the supply chain relationship on supply chain performance and organisation performance. An extensive review of literature identified a lack of empirical research to fill a gap in supply chain and operations management knowledge and this gap is mainly related to identification of the role that trust has on performance. This thesis considers this gap with other relevant issues identified through the literature. It presents a research framework formulated to tackle the research problem and reports an attempt to fill the existing gap through empirical research. The thesis contains analyses of three case studies related to three different territories, namely; Oman, United Arab Emirates (UAE) and State of Qatar. The case studies encompass large and medium size organisations from three different industrial settings. In Oman, the case study is related to oilfield services and the oil production industry while in UAE the case study is related to real estate and the property development industry, and the case study in Qatar is related to the chemical industry. In addition to identifying the influence of trust in supply chain relationships on organisation performance and supply chain performance, the research considers the influence of the duration of the supply chain relationship on trust development in the relationship. Additionally, it explores the impact of trust on the avoidance of the bullwhip effect in the supply chain and shows through empirical evidence the role of trust in minimising supply chain risk. Consideration is given to the impact of different territory and different industrial settings on the trust/performance relationship. Triangulation of research approaches and methods is utilised in this research to enrich the research findings by exploiting the advantages of each approach and method advantages while reducing the disadvantages through complementarities between them. The results of this thesis indicate that the supply chain parties should adopt trust in their relationship whenever considering supply chain performance improvement, organisation performance improvement, and overcoming risk