The evaporation from emulsions is of vital importance for a large number of industrial and technical applications and has, hence, been studied extensively with the recent contributions from University of Hull as leading. The fundamental treatment has evaluated different factors, which influence the evaporation rate for emulsions with sufficiently small surfactant content to retain the 2-phase structure during the evaporation. However, a large number of emulsions have sufficiently high concentrations of surfactant for phase changes to occur within a limited time after the evaporation is initiated. For such systems the phase diagram approach provides a unique opportunity to describe not only the evaporation path and the variation of amount of the compounds in the process, but, more essentially, the changes in the number and amount of different phases. The lecture will introduce this approach and give an example describing a typical emulsion system.