What is the role of environmental performance in port competitiveness? The port industry has often faced governmental mandates for achieving regulatory compliance, including safety, security or environmental requirements. Meeting these requirements has been typically perceived as added costs. Still, some have suggested that a port’s environmental compliance, or even more aggressive environmental practices, could be transformed into a business attribute that would produce an enhancement of a port’s competitive position. With the assistance of desktop research and a survey of existing environmental performance practices, this study examines whether port authorities in practice already endorse this concept, and to what extent, and how, is environmental performance, or might be, a supportive competitive factor for Halifax and other Atlantic Canada ports in their attempt to (re-)emerge as major players for ocean borne trade. The research findings suggest while there is not yet a clear ‘business case’ associating ‘environmental performance’ with direct port competitiveness, Enhancing this performance needs to be prioritized as a mean to address current needs and as an - at least - supportive condition for developing an Atlantic Gateway.