Although uncolored glass can be recycled by the glass industry, mixed glass is normally landfilled. This presents obvious environmental problems, so valorization of mixed glass by using it in concrete is an attractive alternative. When ground to about the same fineness as portland cement, glass powder (GP) demonstrates pozzolanic behavior: the amorphous silica (SiO2) in the GP (Table 1) reacts with portlandite (Ca(OH)2) generated during cement hydration to form gels of calcium silicate hydrate (CSH). Several studies have shown the beneficial effects, including increased workability and reduced chloride permeability, of using GP as a supplementary cementitious material (SCM).1-7 This article provides field trial data on concrete produced with GP. © 2012 American Concrete Institute.