The sixth annual Cornell Hotel Sustainability Benchmarking study finds that participating hotels generally have continued to reduce their energy and water use, although the energy intensity recorded by luxury hotels continues to be relatively high. With information from over 11,000 hotels, the study includes data from substantially more hotels than in all previous years. While the bulk of the data come from hotels in the United States, the study also recorded a greater international participation, with forty-eight nations and seventeen international brands represented. Participating hotels contributed information regarding their energy and water use, as well as greenhouse gas emissions, with data complete as of 2017. While these data permit hoteliers and potential guests to see benchmarks for various hotel segments and locations, individual hotel amenities cannot be accounted for in terms of energy or water use. This year’s study further analyzed the range among data sets to identify the common “efficiency gap range” between the upper and lower quartile among similar hotels, presenting the opportunity and business case for designing and operating energy- and water-efficient hotels. Data collection is now underway for CHSB2020 study, and the authors encourage additional hotels to participate, especially those in the lower tier segments, which are not as strongly represented in these data.