The purpose of this project is to formulate a ''Supercement''designed for improving the long-term sealing integrity in HPHT wells. Phase I concentrated on chemistry studies and screening tests to design and evaluate Portland-based, hybrid Portland, and non-Portland-based cement systems suitable for further scale-up testing. Phase II work concentrated on additional lab and field testing to reduce the candidate materials list to two systems, as well as scale up activities aimed at verifying performance at the field scale. Phase II was extended thorough a proposal to develop additional testing capabilities aimed at quantifying cementing material properties and performance that were previously not possible. Two materials are being taken into Phase III for field testing and commercialization: {lg_bullet} Highly-expansive cement (Portland-based), patent pending as ''Pre-Stressed Cement''{lg_bullet} Epoxy Resin (non-Portland-based), patent pending In Phase II, significant effort was expended on scaling up the processes for handling resin in the field, as it is quite different than conventional Portland-based cements in mixing, personnel protection, and cleanup. Through this effort, over fifty (50) field jobs were done at a variety of temperatures and depths, most with excellent results. Large-scale field testing was less relevant with Pre-stressed Cement, because the materials and surface processes do not vary from those that have been developed for conventional Portland materials over the last eighty (80) years. The formulation is quite unique, however, and performs very differently than conventional Portland cements downhole.