Municipalities are evaluating the potential for low emissions solutions to replace existing diesel-fuelled buses. There are several attractive new technologies on offer in the form of near-zero emissions gas engines. At the same time, electric battery bus technology is developing fast and several demonstration projects are underway. There is an absence of high-quality up-to-date information to inform decision making from fleet operators and local governments. This project therefore aims to provide an up-to-date view on the environmental and economic benefits of compressed natural gas (CNG) and battery electric buses with a particular focus on the Province of Alberta.