• Following the previous four successful ABaCAS conferences, the 5th Air Benefit and Cost and Attainment Assessment Conference (ABaCAS 2017) will be held on July 3-5, 2017 in Chengdu, China. This conference is hosted by Sichuan Academy of Environmental Sciences and Environmental Scientific Society of Sichuan Province, and organized jointly by Tsinghua University, South China University of Technology, Zhejiang University, and University of Tennessee with the support from China Ministry of Environment, U.S. Environmental Protection Agency and Energy Foundation (U.S). The Conference aims at providing a high-level platform for air quality scientists and policy makers from various disciplines to exchange ideas and views on key leading issues related to environment and energy in China, Asia, and all over the world. In addition to the two-day conference (July 4-5), a one-day training workshop(July 3) on the “Air Benefit and Cost and Attainment Assessment System (ABaCAS) will also be provided to air quality managers and scientists of interest with demo and hands-on sessions on cutting-edge air quality management and assessment tools.