We report on simultaneous, common-volume observations of Ca and Ca+ layers in the 80 to 125 km altitude range by groundbased resonance lidar. The measurements were carried out during 9 nights in summer 1995 on the German island R¿gen (55 ¿N,13 ¿E). We observed a permanent Ca layer with an average peak density of 31 atoms/cm3 at 87 km altitude. The average Ca column abundance was 2.2¿107 cm-2. No permanent Ca+ layer was found, but sporadic Ca+ layers occurred frequently in the altitude range 90--120 km. Peak densities of these thin layers varied between 65 and 3900 atoms/cm3. We demonstrate the interesting possibilities of groundbased simultaneous common-volume observations of neutral and ionized calcium in the lower thermosphere. ¿ American Geophysical Union 1996