This program was directed toward (1) establishing a familiarity with basic mix and sample preparation techniques, (2) material characterization, and (3) structural analysis of sulfur concrete mixtures using binders plasticized at 5, 10, 20, 30, and 40 percent. Suitable concrete specimens were prepared using the five binders. For mix design operations, the marshall or hveem procedures for asphaltic mixtures were found to be acceptable. For tests requiring larger size specimens such as unconfined compression and repeated- load creep, the California dot test method 304 is preferred. Sulfur concrete mixtures were subjected to a characterization testing program designed to provide input to a linear viscoelastic pavement design system. A comparison of pavement performance characteristics such as rutting, roughness, cracking, and serviceability of sulfur concrete materials and asphaltic concretes indicated the former could be expected to behave as well as, or superior to, conventional pavement systems. The potential of an in situ characterization device called the duomorph was investigated for monitoring property changes in the five modified-sulfur binders. An apparatus and testing procedure is described for measuring moduli of these binders over a range of test temperatures and loading rates.