I review the currently available techniques for the starspots detection including the one-dimensional spot modelling of photometric light curves. Special attention will be paid to the modelling of photospheric activity based on the high-precision light curves obtained with space missions MOST, CoRoT, and Kepler. Physical spot parameters (temperature, sizes and variability time scales including short-term activity cycles) are discussed.

We report the results of our study of magnetic fields in a sample of Be stars using spectropolarimetric data obtained at the European Southern Observatory with the multi-mode instrument FORS 1 installed at the 8m Kueyen telescope. The detected magnetic fields are rather weak, not stronger than ~150G. A few classical Be stars display cyclic variability of the magnetic field with periods of tens of minutes.

We identify Spectroscopic differences between roAp stars and Ap stars with no observational evidence for pulsation, but with otherwise similar T eff and log g values. These differences concern the abundance pattern, Hydrogen line profile anomalies, evidence for stratification, and effects of pulsation on spectral lines.

A spectroscopic survey of roAp stars has been initiated in Vienna in order to determine their fundamental astrophysical parameters and abundances. We report here on our attempt to confirm and elaborate an atmospheric peculiarity recently discovered (Ryabchikova et al. 1999) which should allow to identify roAp stars with a single spectrum.

We have calculated synthetic spectra for HR 1099 for the wavelength region λ6425-6445 Å, which includes the Cal λ6439 Å and FeI λ6430 Å lines, often used for the surface imaging of rapidly rotating late-type stars. The best agreement between the theoretical and observed spectra can be achieved with solar abundances in the both components of the system, except for Ca in the primary. Theoretical calculations give the possibility of estimating the influence of microturbulence, damping and blending on Ca I and Fe I line profiles.