ABSTRACTRecent advances in high–resolution low–energy electron diffraction (HRLEED) techniques have led to a new capability which provides both very high spatial and temporal resolutions to probe quantitatively the equilibrium and dynamical processes that occur on surfaces and growth fronts. These techniques are especially powerful when the surface or growth front contains atomic steps. Different distributions of steps give different surface atomic pair correlation functions and therefore different angular profile shapes in the diffraction pattern. Recent examples of quantitative HRLEED study of low index plane equilibrium roughening and preroughening transitions are presented. In the growth dynamics, both two–level and multilevel step structures are considered. Examples of the measurements of growth exponents and dynamics scaling are presented.