Green‐lean‐six sigma (GLSS) is an evolving strategy that can be applied in the manufacturing context to address pressing environmental issues. However, due to a lack of research in this area, investigating the motivations behind GLSS implementation is crucial to develop a deeper understanding of factors that shape the overall environmental management strategy of a firm. Drawing on the natural‐resource‐based view and institutional theory, we explore the GLSS drivers and compare developed and developing country contexts by conducting in‐depth interviews with senior consultants specializing in GLSS implementation from New Zealand (NZ) and Pakistan (PK). Findings reveal that the key drivers of GLSS adoption in NZ are general environmental awareness, creating a company image, and government pressure, whereas the main drivers for PK include cost reduction, international customers' influence, and competitiveness. These findings throw light on the reasons for GLSS adoption in different regions and have significant theoretical and practical implications towards improving environmental performance.