Nano-sized objects can be transformed in numerous ways to alter their characteristics. Drug molecules sized in nanometre range provide some unique features which can lead to prolonged circulation, improved drug localization, enhanced drug efficacy etc.; and these increased performance come through a variety of dosage forms. In fact, wide spectrum application of nanotechnology in pharmaceutical formulations is changing the scientific landscape of prevention, diagnosis and treatment of diseases. Various pharmaceutical nanotechnology based systems which can be termed as Nanopharmaceuticals like liposomes, carbon nanotubes, quantum dots, dendrimaers, polymeric nanoparticles, metallic nanoparticles etc. have brought about revolutionary changes in drug delivery as well as the total medical service system. The present review summarizes the most important applications of nanotechnology in drug delivery systems.