General routes to the development of innovative, multi functional nanosystems are described by experts in the field. The systems described are based on fullerenes, nanotubes, metals (Au, Ag, Pt, etc.) and semiconductors (Si, CdS, CdTe, metal oxides), nanocrystals and polymer / biopolymer assembly systems. The book also discusses the realization and characterization of the fundamental properties of nanosystems, defined by nano-size effects, as well as the application of such systems in electronics, optics, magnetoelectronics, spintronics, biomedicine, pharmaceutical biocomplexes, and biosensors.