  We review the Schwarzschild orbit-superposition approach and present a new
implementation of this method, which can deal with a large class of systems,
including rotating barred disk galaxies. We discuss two conceptuals problems in
this field: the intrinsic degeneracy of determining the potential from
line-of-sight kinematics, and the non-uniqueness of deprojection and related
biases in potential inference, especially acute for triaxial bars. When applied
to mock datasets with known 3d shape, our method correctly recovers the pattern
speed and other potential parameters. However, more work is needed to
systematically address these two problems for real observational datasets.
