The Journal features mainly original research work in experiment, theory and applications related to nanophotonic structures. Papers suitable for publication significantly advance our understanding of nanophotonic materials and structures and cover topics such as: • Metamaterials and metasurfaces; • Photonic crystals and related micro- and nanophotonic materials; • Investigation and characterization of photonic crystal properties such as optical nonlinearities, photonic band gap effects, spontaneous emission; • Fabrication of nanophotonic structures and devices using various methods, including lithography, self-assembly, holography, etc.; • Subwavelength optics of structured materials; • Metallic and metallo-dielectric nanophotonic structures; • Subwavelength structures for terahertz optics; • Plasmonics; • Chiral and bianisotropic media; • Structured photonic topological insulators and optics of PT-symmetric nanostructures; • Optics of nanostructured 2D materials; • Random and complex structured optical media; • Frequency selective surfaces; • High-impedance surfaces; • Metamaterials for antenna and circuit technology; • Metamaterial-based devices; • Acoustic and elastic metamaterials; • Photonic crystal fibers and "holey" fibers; • Integration of photonic crystals; • Micro-optical-electro-mechanical-systems (MOEMS); • Nanostructured optical microcavities and photonic "dots"; • Inverse design and machine-learning-driven design of nanophotonic structures; • Novel approaches to micro- and nanophotonics; • Critical assessment of new application fields (light sources, lasers, biophotonics, detectors, optical components, atom and molecule confinement).