Abstract
Through three examples, we illustrate the importance of complementarity between photometry and spectroscopy in studying dynamical processes like stellar pulsations. Analyzing large photometric time series, we get an exhaustive description of the complicated frequency patterns shown by two multiperiodic 6 Scuti stars (EG Vir and X Cae). Simultaneous spectroscopic observations allow us to investigate the different characters of the respective dominant modes: a radial pulsation in FG Vir and nonradial prograde waves in X Cae. The puisational behaviour of X Cae might be connected with some mass loss indication. Probable propagation of prograde waves to the circumstellar region in the presence of mass loss has been detected through spectroscopic observations in the Be star 28 Cyg.
