Sustainable purchasing has become and increasingly salient way by which local governments can decrease their resource consumptions, while also addressing broader climate action goals. Successfully implemented sustainable purchasing policies have the potential to reduce consumption and waste, expand green purchasing markets, and catalyze spillover benefits such as financial savings. Furthermore, city-level actions have become increasingly significant as the federal government ceases critical climate research and pulls out of collaborative climate deals (i.e. The Paris Climate Accord). Using data from the Sustainable Purchasing Researching Initiative at Arizona State University’s Center for Organization Research and Design, as well as qualitative policy analyses, the author investigates the elements of a city’s sustainable purchasing policy (SPP) that are related to its implementation success. Furthermore, the author compares these initial findings to the case study of Phoenix, AZ where she explores whether these elements are also present in the City of Phoenix’s sustainable purchasing policy. The author finds that six key policy elements are generally associated with higher SPP implementation success rates — mandatory requirements, accountability, multi-level governance, vendors requirements, advocacy, and continual improvement. While additional policy elements undoubtedly play a role in the successful implementation of a SPP, the author concludes cities that incorporate these specific elements are better positioned for successful and sustainable implementation. Conclusions further show that the City of Phoenix’s 2007 EPP contained only two of these policy elements. As a result of this project and the author’s work with the City, the 2017 revised SPP incorporates all six policy elements.