Condensable particulate matter (CPM) is one of critical primary components of PM2.5. Formation of CPM is highly dependent on ambient conditions and precursor compositions, and conventional mass-based regulatory frameworks have limited to apply for CPM due to its physicochemical properties. Many countries including Republic of Korea have made efforts to establish the standard measurement protocols and revise current regulations on PM emissions. This paper comprehensively reviews recent research trends in the measurement techniques and emission characteristics of CPM emitted from both stationary and mobile sources. Conventional pollution control systems for stationary sources have focused to reduce only filterable PM (FPM). For mobile sources, both CPM and FPM have been evaluated as emission factors of total PM, not separate ones. In addition, traditional mass-and-number standards are not suitable to determine ultrafine, semi-volatile nucleation-mode particles under transient driving conditions for mobile sources. Therefore, on-line, real-time and size-resolved measurement technologies have been developed to conquer the problems by extending the current measurement upper detection limits and monitor of sub-23 nm volatile CPM particles. This review also highlights the necessity of standard measurement methods including real-time size-distribution metrics, providing a vital technical foundation for high-resolution emission inventories and next-generation air quality standards.