DIETER RASCH, PhD, is scientific advisor at the Center for Design of Experiments at the University of Natural Resources and Life Sciences, Vienna, Austria. He has published more than 275 scientific papers and 56 books as author or editor. DIETER SCHOTT obtained his PhD in analysis from the University of Rostock in 1976 and did his habilitation in the field of numerical functional analysis in 1982. He has published more than 100 scientific papers and is active as author, co-author and editor of numerous books and scientific journals.