We investigate nanoscale and nanostructured systems in the framework of theoretical physics. The main focus of our research is on the electronic transport properties of nanosystems, including effects of quantum interference, strong interaction, and disorder, as well as phenomena far from equilibrium. We are particularly interested in identifying the novel behavior that is of potential use in applications. We develop and employ the most advanced analytical (field-theoretical) approaches, as well as modern computational methods, including ab initio theories of nanosystems. The following describes some of our projects in more detail.