Unimplemented creative ideas are potentially wasted opportunities for organisations. Although it is largely understood how to encourage creativity among employees, how to ensure this creativity is implemented remains underexplored. The objective of the current study is to identify the underlying mechanisms that explain the relationship between high-performance work systems and creativity implementation. Drawing from the job demands–resources model, we explore a model of psychological capital and psychological safety as mediators in the relationship between high-performance work systems and creativity implementation. Based on 505 employee survey responses, the findings show support for the mediating relationships, highlighting the importance of psychological mechanisms. The study has important implications for HRM, uncovering how people management practices can encourage creativity implementation in the workplace.