Jan P. Skalny studied chemical engineering at Slovak Technical University in Bratislava and at the University for Chemical Technology in Prague, where he graduated in 1958. He received his PhD at the University of Mining & Metallurgy in Krakow. In 1967 he left for the United Kingdom and in 1968 he settled with his family in the United States. After a short stay at the Clarkson University in upstate New York, he focused his career on industrial research management. He became Associate Director of Martin Marietta Laboratories and construction materials research director for W. R. Grace & Co. After early retirement in 1991, he became a consultant and is presently President of Materials Service Life, a high-tech consulting company specializing in service life prediction of concrete-based infrastructure. Sidney Mindess is Professor Emeritus at the University of British Columbia, where he has taught in the Department of Civil Engineering since 1969. He holds a PhD from Standford University. His teaching and research interests are primarily in cement and concrete technology, with a particular interest in fiber-reinforced concrete and the behaviour of concrete under impact loading. He has published extensively and is engaged in consulting on concrete construction problems.