  Recent years have witnessed a substantial increase in our ability to trace
the spatially resolved properties of rapidly star-forming galaxies in the
high-redshift universe and numerous studies have suggested the importance of
turbulent gas-phase kinematics. In this submission to the Astro 2010 Decadal
survey we outline some of the major outstanding questions regarding the
kinematics and formation history of these galaxies, such as the prevalence of
various kinematic models, the relation to lower surface-brightness populations
and faint AGN, and the implications for the evolution of gas accretion and
cooling mechanisms with redshift. We comment on the capability of future large
optical/IR and millimeter wavelength facilities to address these questions.
