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As the only low-mass disk galaxy in the Local Group comma M33 is one of the most important and best-studied galaxies on the sky. It is also one of the most confusingdoublePoint since it is nearly bulgeless comma it is unclear what makes it stable to formation of a strong bar. One stabilizing factor may be the existence of dynamically hot components such as a thick disk or halo comma but these have long been controversial and hard to detect. Recent individual-star spectroscopy now gives clear evidence of a halo component comma but its structural properties comma its origin comma and its dynamical effects are not yet clear. We propose to use proper motions with 16-year baselines to measure the kinematics of stars in five fields at the edge of the M33 disk. We will probe the relative rotational lag of the hotter components (the halo and a possible thick disk) versus the young comma thin disk. We will measure the dispersions in the planar and vertical directions separately comma using dispersions measured directly from proper motions as well as the correlation between the proper motions and LOS velocities from spectroscopy. We will check the halo for non-equilibrium flows indicating a possible origin in a recent merger. We will also provide an independent and more precise measurement of M33.s center-of-mass proper motion. These observations are only feasible now because of the longevity of HST. They will yield a dataset completely unique in nature for any galaxy like M33 comma which will shed new light on the structure and dynamical history of this important galaxy.