The Social Internet of Things (SIoT) represents a paradigm shift in the Internet of Things (IoT), where devices autonomously establish social-like relationships to enhance functionality, collaboration, and decision-making. Trust management emerges as a pivotal component in ensuring the reliability, security, and efficiency of SIoT systems, as interactions among devices are influenced by dynamic and often unpredictable factors. This chapter explores trust management from a social perspective, emphasizing how trust mechanisms inspired by human social networks can be applied to enhance SIoT systems. Key topics include the modelling of trust relationships among devices, integrating context-awareness, reputation systems, and behaviour analysis. Additionally, the chapter addresses challenges such as scalability, privacy, and malicious behaviour, proposing innovative frameworks and algorithms to mitigate these risks. By adopting a social approach, this chapter highlights the potential of trust-based interactions to foster more robust, adaptive, and user-centric SIoT ecosystems. Through case studies and practical applications, it demonstrates how trust management can empower devices to collaborate seamlessly, paving the way for a secure and sustainable future in the SIoT landscape.