Wayne W. Frenier recently retired from Schlumberger after more than 30 years of research and development activities in the energy industry. His most recent assignment was as a Schlumberger advisor in product development in Sugar Land, Texas. Frenier is the author of 28 US patents, two books, and numerous technical articles. He holds an MS degree in chemistry from the University of Chicago and is a member of SPE, NACE International, and the American Chemical Society. Murtaza Ziauddin is a principal engineer with Schlumberger and works on research and development projects in the areas of organic and inorganic scale, matrix stimulation of sandstones and carbonates, enhanced oil recovery, and CO2 sequestration. He also has led the development of a geochemical simulation software for matrix acidizing and inorganic scale prediction. Ziauddin is the author of numerous technical articles and two US patents; he joined Schlumberger in 1997 after receiving a BS degree from the University of Houston and a PhD degree from the University of Minnesota, both in chemical engineering. He is a member of SPE and several other engineering societies.