The research activity of our group focuses on the synthesis and design of functional molecular hosts and devices, which can bind, detect or transport guests with high selectivity. The host design is accomplished in our laboratory by theoretical calculations, supramolecular synthesis and self-assembly processes. Exploring the properties of new functional hosts provides extremely valuable knowledge to understand Nature. The designed systems have found applications in sensing of biologically important species and extraction/recycling of environmentally relevant ions, as well as in visualization of ion transport and signal transduction processes in living organisms. We make a particular effort to invent systems that function in water in order to study them in biological systems and as supramolecular catalysts to enable new chemical transformations. Our molecular devices have potential to face the challenges such as energy conversion, molecular logic gates and memory devices.