Glass Surface Structure and Durability: Fundamentals and Applications The durability of glass and glass-based products is a primary concern in all engineering/technical applications as well as in nature. In particular, silicate glasses are of interest for; (1) rare-earth-doped optical fibers and devices, (2) flat-panel display glasses, (3) reinforcement fibers for plastics, (4) glasses for nuclear waste products, (5) glasses used in solar energy applications, and (6) glasses for a wide variety of commercial and residential windows. Throughout their processing and service lifetime, they are exposed to aqueous solutions and/or humid environments. Resultant changes that occur on the glass surface can effect many properties including; adsorption behavior and coatability, optical properties, surface finish, product lifetime, and mechanical strength. Furthermore, changes that occur on a final, coated glass product due to these same conditions can effect its’ functionality and performance. Therefore, understanding of such corrosion behavior is or great interest and importance. In this presentation, through the use of a host of analytical tools as well theoretical modeling, the fundamental link between bulk composition and structure, surface reactions, and functionality of common silicate-based glasses will be investigated. In addition, examples of current commercial products where surface structure and durability are critical, yet currently poorly understood, will be given.