Natural ion channels are of outstanding importance in all living cells. Based on them more and more artificial ion channels are prepared for many biomedical and bioengineering applications, separation devices, environmental monitoring, food safety and so on. Moreover, the comprehensive study of their mechanism of action can lead to deep understanding of life at the cellular level. Unfortunately, ion transport across lipid bilayer membranes is an elusive phenomena difficult to evidence. This review focuses on the main techniques suitable to evidence it starting from liposomes as biomimetic model for the cellular membrane and going to the use of fluorescence spectroscopy to study membrane active molecules.