The creation of membranes is of enormous importance in biology, but also in many chemical applications developed by humans. These membranes are shaped spontaneously when soap-like molecules in water join together. Researchers at Eindhoven University of Technology now have a clear picture of the entire process. Membrane formation turns out to start with nano-droplets in the water with a higher concentration of soap-like molecules. If you can control those nanodroplets, you can control shape, thickness and size of the membranes. This is of great importance for, among other things, the development of new nanomedicines. The results are published in Nature Chemistry.