  We present kinematics of a sample of 107 DA white dwarfs from the SPY project
and discuss kinematic criteria for a distinction of thin disk, thick disk, and
halo populations. This is the first homogeneous sample of white dwarfs for
which 3D space motions have been determined. Studies of white dwarf kinematics
can help determine the fraction of the total mass of our Galaxy contained in
the form of thick disk and halo white dwarfs. Radial velocities and
spectroscopic distances obtained by the SPY project are combined with our
measurements of proper motions to derive 3D space motions. Galactic orbits and
further kinematic parameters are computed. Candidates for thick disk and halo
members are selected in a first step from the classical U-V-velocity diagram.
Our final assignment of population membership is based on orbits and position
in the angular-momentum-eccentricity diagram. We find four halo and twelve
thick disk white dwarfs.
