  Spectroscopy from the final internal data release of the Gaia-ESO Survey
(GES) has been combined with Gaia EDR3 to assign membership probabilities to
targets observed towards 63 Galactic open clusters and 7 globular clusters. The
membership probabilities are based chiefly on maximum likelihood modelling of
the 3D kinematics of the targets, separating them into cluster and field
populations. From 43211 observed targets, 13985 are identified as highly
probable cluster members ($P>0.9$), with an average membership probability of
0.993. The addition of GES radial velocities successfully drives down the
fraction of false positives and we achieve better levels of discrimination in
most clusters over the use of astrometric data alone, especially those at
larger distances. Since the membership selection is almost purely kinematic,
the union of this catalogue with GES and Gaia is ideal for investigating the
photometric and chemical properties of clusters as a function of stellar mass,
age and Galactic position.
