One of the challenges in developing a consensus around the goal of sustainable transportation is a lack of consensus around the terms used to define and describe sustainable transportation. The goal in this project was to assemble a list of relevant terms and provide clear and simple definitions. Because it is not uncommon to find multiple terms used to refer to the same concept, the report also aims to differentiate the preferred terms from less preferred terms and terms that should not be used for various reasons. Terms were identified based on a review of documents from transportation agencies, websites and publications from transportation organizations, and papers published by the academic community, and refined the list in consultation with Ellen Greenberg, Deputy Director of Sustainability at the California Department of Transportation (Caltrans). Terms are grouped into categories based on purpose, mode, destinations, community type, and others. The intent of this work is to create a useful resource for those working to advance sustainable transportation