I. Flare Stars. Optical Observations and Flare Statistics.- Flare stars in star clusters, associations and solar vicinity (Invited paper).- The flare activity of AD Leo1972-1988.- Photometrical, spectral and radio monitoring for EV Lac in 1986 and 1987.- Electrophotometric observations of the EV Lac flares in U, H? and H?.- Rapid spike flares on AD Leo and EV Lac.- Photoelectric observations of flares on UV Ceti.- Two-colour observations of spikes and flares with high time resolution.- A short-lived flare on EV Lacertae.- Diagnostic possibilities of the Walrawen photometric system.- The flare activity of two peculiar red dwarfs.- Statistics of flares observed for UV Ceti type stars YZ CMi, AD Leo, and EV Lac at the Okayama Observatory.- Flare activity levels for fully convective red dwarfs.- Some physical consequences from the flare statistics of the UV Cet type stars in the solar neighbourhood.- Search for slow light variations of red-dwarf stars.- Distribution of red dwarfs in general galactic field on the basis of stellar star statistics.- New observations of flare stars in the Pleiades by the method of stellar tracks.- Possible new, bright flare star in the Pleiades region.- Data filtering in statistical studies of flares recorded in sky fields of stellar aggregates - demonstrated with the example of the Pleiades.- On two possible groups of flare stars in Pleiades.- Flare activity of stars in the Taurus region.- An automatic search for flare stars in southern stellar aggregates of different ages.- Spectral observations of flare stars.- NTT spectra of the flare stars HM1 and HM2 in the R Coronae Austrinae aggregate.- Catalog of flare stars in Orion nebula region.- A catalogue of flare stars in the Cygnus region.- Slow flares in stellar aggregates and solar vicinity.- A prediction of the flare activity of stellar aggregates.- Flare stars as age indicators in open clusters.- The relative number of flare stars in systems of different ages.- Flare stars at radio wavelengths (Invited paper).- Broadband spectral radio observations of flare stars.- Radio flare on eta Gemini star.- X-ray emission from solar neighbourhood flare stars.- Balmer and soft X-ray emission from solar and stellar flares.- X-ray variability in the Orion nebula.- II. Flare Stars and Related Objects. T Tauri Stars..- Some resolutions on T Tauri stars (Invited paper).- The variability of T Tauri stars.- Periodical variations of the brightness of T Tauri.- The polarization discovery and investigation of T Tau stars in Byurakan.- Recent results on polarization of T Tauri stars and other young stellar objects.- The UBVRI photometric and Polarimetric observations of the T Tau star HDE 283572.- Axial rotation of BY Dra-type stars and related objects.- Flares on T Tauri stars (Invited paper).- T Tauri stars and flare stars: common properties and differences.- Circumstellar phenomena and the position of T Tauri stars in the colour-magnitude diagram.- High resolution spectroscopy of RY Tauri: variability of the Na D line profiles.- Herbig-Haro phenomena associated with T Tauri: evidence for a precessing jet?.- Survey observations of emission line stars and Herbig-Haro objects at the Kiso Observatory.- III. Flare Stars and Related Objects. Fuors and Other Non-Stable Objects..- FU Orionis eruptions and early stellar evolution (Invited paper).- Subfuors in Orion association.- Slow flares and eruptive phenomena in early stages of stellar evolution.- A new fuor?.- Correlation between flare stars and other populations in young clusters and star forming regions.- The results of spectral observations of collimated outflows.- H2O megamaser in Orion KL.- Flares of radio line emission H2O in Ori A and W49N.- On the connection between the IRAS point sources and galactic nonstable objects.- The statistical analysis of the optical and infrared luminosities of young stars.- Far infrared emission from post-T Tauri stars.- Residual extinction effects in spectra of newly formed stars.- IV. Theoretical Problems and Interpretation of Observations..- Review of the theoretical models of flares of the UV Ceti-type stars (Invited review).- Quiescent chromospheric response to the (E)UV/optical flare radiation field on dMe stars.- The hydrogen atom kinetics in flare star chromospheres.- The Balmer decrement in red dwarfs spectra during the flares and quiescent state.- A model for the observed periodicity in the flaring rate on YY Gem.- Pinch-model of flares and its observational consequences.- On the gamma-activity of stellar flares.- On a differential equation for electromagnetic wave transmission in flare stars and the possible existance of cohesive wave solutions.- The stochastical approach to the modelling of the line profiles in T Tauri stellar winds.- On the origin of dwarf stars (Invited review).- Magnetic activity and evolution of low-mass young stars.- V. Prospects for Stellar Flare Research and Concluding Remarks..- Prospects for studies of UV Cet-type flare stars (Invited review).- Closing remarks.- Author index.- Object index.