A comprehensive review of ongoing and recommended research directions concerning the structure, dynamics, and interfacial activity of synthetic and naturally occurring macromolecules at the solid-liquid interface is presented. Many new developments stem from the ability to target new size regimes of 1-100 nm. These rapid developments are reviewed critically with respect to chemical synthesis, processing, structural characterization, dynamic processes, and theoretical and computational analysis. The common problems shared by flat and particulate sur-faces are emphasized. A broad spectrum of material properties are discussed, from the control of interfacial friction between surfaces in moving contact, to the mechanical strength and durability of the interfaces in hybrid materials, to optical and electronic properties. Future-research opportunities are identified that involve (1) the emergence of nanoscale material properties, (2) polymer-assisted nanostructures, and (3) the crossroads between interfacial science and biological and bioinspired applications. (C) 2003 Wiley Periodicals, Inc.