The macroscopic forms of interfaces in condensed matter systems are often determined by microscopic effects (such as crystalline anisotropy, the binding energy of atoms to the surface, or random pinning of the interface by inhomogeneities). Therefore, studies of interfacial shapes can lead to fundamental insights. This project is especially concerned with interfaces in non- equilibirum systems. It is intended to establish (a) the degree to which proven concepts developed for equilibrium systems are useful in understanding those driven away from equilibrium and (b) the degree to which a macroscopic continuum explanation of interfacial patterns is possible. Three major areas of investigation are planned: (1) the kinetic roughening of faceted crystals, in which crystal shapes become rounded during growth; (2) the growth of dendritic crystals (snowflake-like structures) and other complex interfaces, especially the role of crystalline anistropy and the development of complex patterns; and (3) the form and dynamics of a fluid interface moving in a random porous medium. The experiments will utilize high precision digital image processing methods developed at Haverford during the previous grant period. This RUI project will employ collaborations between graduate and undergraduate students, both to enhance the effectiveness of undergraduate research and to help address the severe shortage of capable researchers interested in undergraduate education.