Optical interference coatings have become a key enabling technology for many laser systems. Modern oscillators and amplifiers are capable of generating ultrashort pulses with energies of several tens of µJ at repetition rates of more than 10 MHz, resulting in several hundreds of watts of average output power. Under the illumination of optical coatings by such intense optical fields, the nonlinear effects manifest themselves. These effects can be exploited for development of novel types of nonlinear optical (NLO) laser components: dielectric multilayer coatings with specified nonlinear properties. In order to use the potential of dielectric coatings as NLO devices, the nonlinear behaviour of dielectric multilayers at intensities which are, from one side, high enough to activate nonlinearities and lower, from other side, than laser damage threshold, has to be carefully explored. As structures of films differ from the ones of bulk materials, then characterization of nonlinear effects in dielectric coatings is to be carried out and numerical values of coatings’ nonlinear parameters are be estimated.NICOS project is aimed at accurate and reliable characterization of nonlinear effects in dielectric coatings and development of new types of NLO dielectric multilayers for laser applications. In order to resolve project tasks, a combination of four main elements is required: (1) laser systems to generate high intensity pulses inducing nonlinear effects in multilayers, (2) deposition plants to produce the coatings, (3) measurement tools to characterize the effects and (4) background in modelling and optical technology. Unique research facilities of the Host Institution together with Applicant’s expertise in optical coatings provide a basis for successful implementation of the project. The results of NICOS will be a valuable contribution to nonlinear optics, laser physics and thin film technology. NICOS will assist in pushing frontiers in promising laser components.