Grid computing that has developed with the aim of high-end computing has extended to commercial areas as the enabler of cost and risk minimization for IT resources. To actualize larger benefit from Grid by widening Grid adoption, the formation of trust relationship among participants is one of the most important components that should be concerned. While trust mechanisms among distributed nodes have been studied, the related works are rather theoretical and conceptual than applicable to practical commercial Grid. Based on this observation, we classify trust depending on distinctive requirements in practical Grid utilization, and improve the evaluation process of trust by suggesting integrated measuring methods. We also introduce the ways for practical use of evaluated trust by guaranteeing individuals? manageability. Finally, we describe the process for eliciting system constituents? trust requirements and validating suggested architecture, which will be conducted in the next phase of this research.