The 12 to 20 metre baseline interferometer at C.E.R.G.A. built by A. Labeyrie has now been operational for two years. The purpose of this instrument was initially to be a prototype showing the feasibility of long baseline coherent arrays and for testing the techniques needed for them. Yet, pending completion of large interferometers, this small 2 x 26 cm instrument has proven able to yield astrophysical data: a dozen stars up to third magnitude have been observed with a 3 x 10-3 arc second resolution on diameters and a 5 x 10-4 arc second accuracy for binary separation measurements in the case of α Aur.
What has been observed both from the technological and the astrophysical point of view will be discussed.