Chalcogenide glasses (CHG) have attracted the attention of researchers since 1960´s and have been exploited in various fields due to their unique properties and functionalities. They are widely used, for example, in infrared optical components and for optical recording in DVD´s, CD´s and blu ray discs and they are very promising materials for all-optical functionality systems. In comparison with “classical” oxide glasses they possess significantly lower rigidity, lower softening temperature and unusual photosensitivity. Numerous photoinduced phenomena suitable for novel applications, such as: photo-polymerization, photo-decomposition, local atomic restructuring, photo-crystallization, photo-contraction or photo-expansion, photo-fluidity, photovaporization, photo-plasticity, photo-dissolution of metals, etc. can be exploited. The nature of the photoinduced phenomena depends not only on glass composition and its prehistory, but also on the type of radiation and conditions of its interaction with chalcogenide thin film. Suitable radiation for producing photoinduced phenomena is mainly visible light with energy comparable or slightly greater than the optical band gap of the chalcogenide film, but UV light, X-rays, ions and/or electrons can induce some of above mentioned phenomena as well. In all cases, radiation-induced change causes significant changes of optical and physico-chemical properties, which can be exploited in the fabrication of photonic devices using, for example, consequent dry or wet selective etching. A rapid, single step process for fabricating functional diffractive optical elements on CHG is also possible using high power focused laser beam. In this paper we summarize our results with regard to 3D structuring of thin chalcogenide films using either exposure with photons/electrons with consequent wet/dry selective etching or using direct laser writing methods. Possible mechanisms of photons/electrons interaction with thin chalcogenide thin films and mechanisms of their selective etching are given on the base of complex studies of radiation induced structure/properties changes (various methods such as UV-VIS, Raman, IR, XPS, X-ray absorption spectroscopy, DTA, DSC, AFM were exploited). Possibilities, advantages and limits of various methods for 3D micro- and nanostructuring of chalcogenide thin films are discussed and examples of practical application for fabrication of various diffractive optical elements are given. Acknowledgement: This work was supported by the grant P204/11/0832 from the Czech Science Foundation. The authors thank U.S. National Science Foundation, through International Materials Institute for New Functionality in Glass, for supporting their international collaboration for this work (NSF Grant No. DMR-0844014).