["Business Strategy and the Environment, Volume 35, Issue 3, Page 3422-3444, March 2026. ", "\nABSTRACT\nGrowing environmental challenges have increased the demand for employee‐driven innovation to support organizational sustainability. Drawing on the Ability–Motivation–Opportunity (AMO) framework, this study explores how individual‐level proactive personality (PP) and organizational‐level high‐involvement green human resource management (HI GHRM) practices interact to foster employees' environmental creative performance (ECP). This study conceptualizes and measures HI GHRM as a five‐dimensional model integrating green HRM and high‐involvement HRM concepts. This study adopted multilevel analysis with data collected from 136 firms and 680 employees in Taiwan's environmental protection industry. The results show that PP has a significant positive impact on ECP, highlighting the importance of proactive traits in fostering creative environmental solutions. However, HI GHRM, as a bundled system, does not significantly moderate the PP–ECP relationship. This study contributes theoretical insights by combining strategic HRM and GHRM to propose the concept of HI GHRM. Furthermore, drawing on AMO theory, five dimensions of HI GHRM practices are identified. Additionally, multilevel analysis shows that personality traits and HI GHRM practices jointly influence ECP, emphasizing the role of environmental creativity in sustainability. These findings provide practical guidance for managers and policymakers in adopting HRM strategies that enhance employees' sustainability‐driven creativity.\n"]