This paper reviews the concept of dielectric resonator antennas (DRAs) scaled to nanometer dimensions for operation at infrared and visible wavelength. In comparison to resonant metallic structures which are affected by large plasmonic losses at optical frequencies, dielectric resonator nano-antennas appear very attractive since they are predominantly based on displacement currents. In this context, recent years have seen the emergence of nano-structured optical devices based on fundamental resonances in low-loss dielectric structures. The present paper describes how methods developed at radio-frequencies, in particular the design of DRAs and reflectarrays, can contribute to the creation of efficient devices for the manipulation of light.