Long Baseline Interferometry of Be Stars
  We give an introduction to interferometrical concepts and their applicability to Be stars. The first part of the paper concentrates on a short historic overview and basic principles of two-beam interferometric observations. In the second part, the VLTI/MIDI instrument is introduced and its first results on Be stars, obtained on alpha Ara and delta Cen, are outlined. 
Olivier Chesneau (LG), Thomas Rivinius