Plasmon-based nanophotonics is the study of the interaction of nanometer-scale metallic objects with light. For example, light can be strongly absorbed and scattered by tiny metallic objects (of size much smaller than the wavelength of light), if the incident wavelength or object size and shape are chosen properly - an effect called localized surface plasmon-polariton resonance. Another area of this study is the guiding of the electromagnetic excitation along metal-dielectric interface, when the photon is coupled to the oscillations of free electrons in the metal, called surface plasmon-polariton (SPP). The advantages of SPP waveguides compared to dielectric photonic waveguides are strong field confinement and its localization near the metal surface, which can be applied to dense packing of optical components, sensing, active thermal components, etc.At SDU Nano Optics, we study the properties of plasmonic waveguides and their applications. For example, we demonstrated nanofocusing of the electromagnetic radiation into tiny hot-spots using gradually tapered plasmonic waveguides. Also, we investigate strong field enhancement created by plasmonic nanostructures, which can find immediate application in sensing.