There is an increasing growth of customers and regulators requesting enterprises to adopt the ISO 14001 environmental management standard over the last 15 years. Yet, any evidence for consistent environmental, market, and social benefits has been widely debated, which in turn, might be partly linked to the underlying organizational motives for environmental management system adoption. Based on the Institutional Theory and the Natural Resource-based view, this study examines the relationship of two different organizational adoption motives (i.e., internal and external) with triple bottom line perceived benefits (i.e., environmental, social, and market) on the adoption of ISO 14001. Using empirical data collected from a large-scale survey of Australian firms, we found that the motivation for environmental management system adoption was aligned closely with the types of benefits that accrued. The results indicate that external motives enhance social and market positioning, whereas internal motives better serve environmental benefits. Thus, managers may be seeking only a narrowly bounded set of outcomes from ISO 14001, rather than broader strategic improvement. The results also show the environmental benefits of adopting ISO 14001 to improve both the social and market benefits of the adopter enterprises. Practically, environmental benefits should be realized before firms can expect to reap social and market benefits from the environmental management system adoption. Our investigation on multiple motivations for organizational adoption of a voluntary standard provides important theoretical and practical insights on which organizational environmental management system adoption motives are conducive to fostering a broader set of strategic benefits.