The OPON workshop organized by NLPQT took place on February 12-14, 2020. In accordance with its name, “The 6th International Workshop on the Optical Properties of Nanostructures OPON 2020“, it gathered physicists working on the optical properties of nanostructures. To the workshops came 100 participants from 4 countries. They gave 15 invited lectures as well as 24 contributed oral presentations and 32 poster presentations. The most attention was drawn to quantum dots as a light source for quantum information and advances in the technology of two-dimensional materials, including transition metal dichalkogenides.