Parts 1 and 2 of this article showed that certain reactive surfactants can be used to produce latexes with substantially improved water resistance and repellency, better storage stability, and with better adhesion to metal substrates than latexes prepared with non-reactive surfactants or with other reactives. In Part 3, we show that these same surfactants can be used to build-in freeze/thaw (F/T) stability to latexes and improve the open time of coatings based on them.1 A method to improve the hiding power of latex coatings by using a phosphate ester-based reactive surfactant and, thereby, reduce TiO2 usage is also discussed.