His first folded printed reliefs originate from the 1970s. Gradually, however, Dees developed his own vocabulary in which three-dimensional patterns of folds were layered as an extra stratum over increasingly complex colour etchings and monotypes. Years later, after a period in which he was mainly involved with three-dimensional installations on a much larger scale, paper reliefs re-emerged. This time based on prints of computer-generated collages, which made it possible to achieve an extremely fine balance between abstraction, references and three-dimensionality.