The invention concerns a method and apparatus (100) for producing mist of a liquid phase having very fine and mono-dispersed droplets. The method is realized by an apparatus (100) including a partition (101), defined by a first side surface (107) and a second side surface (113). The first side surface (107) is wetted by a liquid phase to form a film thereon, while the second side surface (113) is substantially dry. A gas stream is directed through the partition (101) from the dry side (113) to the wetted side (107) thereby forming a mist having droplets of less than 1 micron in size and a concentration of at least 1,000,000,000,000 per cubic cm.