  We present an improved orbit determination for the visual pair in the M-dwarf
triple system Gliese 866 that is based on new speckle-interferometric and HST
observations. The system mass is M = 0.34 +- 0.03 solar masses. The masses of
the components derived using the mass-luminosity relation are consistent with
this mass sum. All three components of Gliese 866 seem to have masses not far
from the hydrogen burning mass limit.
