Fusion of lipid bilayers, or membranes, is a ubiquitous process. It occurs in the cells of our body during cargo exchange by membrane vesicles and during viral infection, but also in industrial processes such as yeast production. While many proteins like SNAREs have been identified that play crucial roles in membrane fusion, the molecular mechanism of fusion remains unclear. This fascinating process of membrane fusion is complex and our aim is to understand the details of this process using a biomimetic model system which has all the characteristics of natural membrane fusion; targeted docking, followed by lipid and content mixing in the absence of leakage. Therefore we developed a model system composed of a complementary pair of lipidated peptides able to form a heterodimeric coiled coil motif at the membrane interface similar inspired by natural SNAREs. The different steps of membrane fusion are currently studied using biophysical and biochemical techniques with a special focus on peptide-peptide and peptide-lipid interactions. Recently we optimized our membrane fusion system, which is now also functional with live cells. Initial studies suggest that cargo can be delivered into the cytoplasm/nucleus of cells while avoiding endosomal pathways, which would be an efficient way for drug delivery.