The search for the best asset optimization project has recently led several concentrator plants to select the implementation of a novel particle size tracking technology on individual cyclones due to the deficiencies of existing technologies and the excellent financial metrics, such as a payback period of significantly less than one year. This paper presents the CYCLONEtrac Particle Size Tracking (PST) technology that has been installed in nine large concentrator plants processing copper, iron, gold and phosphate ores. Plant data will be presented showing the benefits of improved process control enabled by using strategies based on individual cyclone measurements, and based on consolidated measurements of the entire cyclone battery. It will also be shown how the technology is well suited for use in ‘coarse grind strategies’ where higher target particle size could present problems for less robust legacy technologies.