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he UX Ori type stars (or UXORs) are the photometrically most active young objects, predominantly Herbig Ae stars. They demonstrate aperiodic algol-like minima with amplitudes up to ∆V ∼ 2-3 mag and duration from a few days to a few weeks. The brightness variations are accompanied by changes in color, linear polarization and spectra. The most natural explanation of the observed phenomena is a model of variable circumstellar (CS) extinction taking into account scattered radiation from the CS disks. The source of the variable CS extinction is the perturbations in the innermost regions of the CS disks. Therefore the photometric behavior of UXORs is an important, and in some respects unique source of information about the dynamical state of these regions. In recent years extinction events on different timescales have been observed in several T Tauri stars. An important step in the study of such objects was made with the help of photometric observations from space: the CoRoT and Kepler missions. They have shown that the small-amplitude extinction events (dips) of different types (periodic or aperiodic) have been frequently observed in T Tauri stars. In this case the main source of the variable extinction are the dusty disk wind and the region of interaction of CS disk with the stellar magnetosphere. The goal of our workshop is to discuss the observational properties of UXORs and related objects in the light of new theoretical models.