At the beginning of this video we will show you two different batch methods for the formation of vesicles and their limitations which were adapted from the liposome preparation techniques. Compared to this, the next presentation of a continuous process for the production and in-situ loading of polymersomes illustrates the outstanding advantages of micro technology for nano engineering. Polymersomes are the synthetic analogues to liposomes and a relatively new kind of soft nanoparticles, which have already shown great promise as drug carriers. They are composed of amphiphilic block copolymers instead of phospholipids like their natural counterparts. Due to the good synthetic control of polymer chemistry, polymersomes provide much more variability, stability and functionality than liposomes. The formation of polymersomes by controlled self-assembly can be induced by transferring the block copolymer in a selective solvent, for example water. In this case hydrophobic parts will associate in order to prevent the unfavorable contact with water, while the hydrophilic blocks will face the inner and outer solution. Due to this association, polymersomes have the capability to load hydrophilic molecules as well as hydrophobic ones, which offers advantages over spherical polymer micelles. Nevertheless, the preparation and loading of polymer nanostructures is a challenging task since it must be a highly controllable and continuous process.