Trust is the cornerstone of success in any relationship between two or more parties. Current technologies to include cloud computing, social networking, and mobile applications, coupled with the explosion in storage and processing power, are evolving large-scale marketplaces for a wide variety of resources and services. In such marketplaces, users (consumer, provider and broker) are largely autonomous with vastly diverse requirements, capabilities, and trust profiles, and thus trustworthy interactions and transactions become a challenging endeavor. We hypothesize the need for a dynamically customizable personalized trust management system for the robustness and wide-scale adoption of such large-scale heterogeneous marketplaces. In this paper, we explore and enable trust personalization and propose PETRA, PErsonalized TRust Architecture, and present a PETRA-based trust management system. Our simulation results demonstrate the effectiveness and efficiency of the PETRA-based approach and illustrate the impact of trust personalization.