An International Aerosol Conference (IAC), held once in every four years, is the largest and most prestigious professional meeting in the aerosol research community worldwide. The 9th IAC was organized by the Korean Association for Particle and Aerosol Research (KAPAR) on behalf of the International Aerosol Research Assembly (IARA) and held from August 31 to September 5, 2014 in Busan, Republic of Korea. A total of 1215 participants from 52 countries presented 1059 papers, including 529 oral and 530 poster presentations. More than a half (51%) of the presentations was from Asia followed by Europe (35%), and North America (15%). The presentations covered a wide range of aerosol-related studies. Among 17 topics, the theme ‘atmospheric aerosols and air quality’ had the most presentations (21% of the total number of papers presented), followed by ‘aerosol chemistry’ (10%), ‘atmospheric aerosols and global climate’ (9%), ‘instrumentation’ (8%) and ‘aerosol physics’ (8%). This suggests that air quality issues related to ambient aerosols is of a major concern, especially, in East Asian countries. In addition to research presentations, various educational and social activities were carried out during the IAC-2014. There were tutorial lectures attended by 166 participants as well as several plenary and keynote lectures given by distinguished speakers. One of the popular social activities was a conference tour to the traditional Korean folk village and Buddhist temples, both are UNESCO world heritage sites. Also, there was a large and interesting exhibition from 29 companies and institutions related to aerosols.