Cities face immense environmental challenges with limited resources to implement management solutions. Relevant trends in the private sector toward third party certification to external environmental management standards have yet to be fully embraced by governing Local Authorities (LAs). As the first city in North America to obtain ISO 14001 certification, the City of Calgary is examined as a case study of the implementation of a certified Environmental Management System (EMS) from impetus through to ongoing effects on learning. Investigation demonstrates that the unique characteristics of LA organizations are important factors in considering the strengths and challenges of using a voluntary external standard to establish environmental priorities. While LAs must avoid overemphasizing the standard itself, an informed approach increases organizational transparency and accountability, and enables collective problem solving. The certification process is a motivating surrogate force for cities which typically lack the competitive pressure found in for-profit sectors.