Summary form only given. Over the last fifty years, lithium niobate (LSTbO/sub 3/) and lithium tantalate (LiTaO/sub 3/) ferroelectrics have emerged as key materials for electro-optics and nonlinear optical devices. Many of these applications require microengineering ferroelectric domains into diverse shapes and length scales. However, until recently no direct probing techniques have been used to study these domain processes in situ. Recently, key breakthroughs have been made in the real-time video observation of the nucleation and growth dynamics of ferroelectric domains under external fields using Electro-Optic Imaging Microscopy (EOIM). The EOIM exploits the electro-optic effect in the material to create a refractive index contrast at a domain wall under external electric fields, which is then optically imaged. We present the direct real-time tracking of the motion of a single domain wall in lithium tantalate and lithium niobate and the measurement of domain wall mobilities and energies associated with the walls.