Airports across the United States are owned and operated by a wide variety of governance structures, each with their own features and historical legacies. As the common refrain from airport professionals goes, if you've seen one airport, you've seen one airport. Similarly, if you've seen one airport's governance structure, you've seen one airport's governance structure. The TRB Airport Cooperative Research Program's ACRP Research Report 245: Guide to Evaluating Airport Governance Structures provides valuable tools to help communities evaluate the effectiveness of their current governance structure and consider alternative governance structures at airports. Supplemental to the report is a web app to search and query an online database of the key governance attributes of more than 98% of the airports in the National Plan of Integrated Airport Systems (NPIAS).