Different types of massive interacting binaries with Be components are discussed. Due to mass exchange, Be stars in these systems have some peculiar characteristics. Often it is even difficult to find traces of the Be star and/or mass-losing star in the optical region of the spectrum. Using the value of the orbital period as a primary parameter, it is possible to divide all massive interacting binaries into two large groups: short-period or classical Algols and long-period binaries. The last group includes a number of very active mass transfer systems named as W Serpentis. There is also a small group of double systems whose stars do not fill their Roche lobes but have emission lines in the spectrum. Properties of their spectral variability are discussed. Analysis of each group lets us find different behaviours in mass exchange that depend on the size of their Roche lobes.

We present optical photometry and high resolution optical spectra of the Be star X Persei/HD 24534, the counterpart to the X-ray pulsar 4U0352+30, obtained over the past ~10 years. These spectra show a variety of behaviour, ending with the onset of a strong V/R cycle. Observations of the He 16678 line suggest several episodes of discrete disc forming. This data forms part of a major long-term multiwavelength monitoring programme (UBVRIJHKL photometry plus optical and UV spectroscopy).

We present results of our long-term monitoring of LS I +61° 235 in the optical and infrared bands. This Be/X-ray binary exhibits V/R variability in the Hα line, which can be explained in the framework of the Global One-armed Oscillation model: a high density perturbation moves around inside the circumstellar disc of the Be star. The V>R and V<R peaks occur when the perturbation moves towards and away from the observer, respectively. In this work we show that the perturbation also affects the He I λ6678Å and Paschen lines. We also report on a correlation between the infrared emission and the V/R variability.

Significant profile variability of Hα on the timescale of months is investigated on the basis of high-dispersion CCD spectra of the B3e Herbig star HD 200775. Variations in position and shape of the central absorption component are considered to indicate complex structure of circumstellar environment, containing infalling streams and inhomogeneous stellar wind.

ɛ Per (45 Per, HR 1220, HD 24760, ADS 2888A) is a star which was used for years as a spectrophotometric and MKK classification standard. Nowadays it is known as an archetype of early-type line-profile variables (LPV). The variations are so pronounced that they were misinterpreted for a composite spectrum (B0.5+A2) and the star was even reported to be a double-lined spectroscopic binary (Petrie 1958). Since 1983, the characteristics of line-profile variability in the spectrum of ɛ Per have been intensively studied (Bolton 1983, Smith 1985, Gies & Kullavanijaya 1988). The recent investigations of RV variations of ɛ Per led to the conclusion that ɛ Per is a spectroscopic binary with a period of about 14.05 days and a rather eccentric orbit (Harmanec & Tarasov 1990). The issue of the binary nature (with a very eccentric orbit) is of utmost importance since it could be causally related to the extremely large observed line-profile variations (e.g., Polfliet & Smeyers 1990, Tassoul & Tassoul 1992).

The light curves in UBVRI and profiles of the emission lines of Hα, HeII 5411 and HeI 5876, 6678 obtained during 1985–87. The radial velocities of the emission lines HeI 6678 and HeII 5411 demonstrated clear periodic variations in antiphase with the radial velocity defined for the absorption line.

Basic information about the star o and (HR 8762, HD 217675-6) is a bright (V=3.55m, B-V=-0.11m U-B=-0.50m) B6 III-Ve star. Its emission-line and shell spectrum is known to come and go on a time scale of years. In fact, the presence of a strong shell spectrum misled the authors of the HD catalogue to assign the star two HD numbers.

o and is a prototype of Be rapid light variables in the sense that it has the longest record of photoelectric monitoring which goes back to 1915! The long history of attempts to understand the variations of this star has recently been summarized by Harmanec (1983). Collecting and analyzing all historical photoelectric observations, Harmanec (1984) concluded that the light variations of o And can be understood as a superposition of a long-term cyclic (8.5y) variation with an amplitude over 0.1m (the star being faintest at the recorded shell maxima) and a rapid periodic variation with a period of 1.571272 days.

The profiles of the emission lines of Hα, HeI 587 6 and HeII 5411 in the spectrum of AG Peg obtained in the minimum of 1985 are described. The light curves in UBVRI system are presented. No indication for the presence of a magnetic field exceeding the error of observations (200 gauss) has been found.