With the exception of the emergence in the 1960s of process art, which tried to present creative activity as the product, most artists, historians, and critics have been content to let this aspect of art production remain submerged in mystery and intrigue. The continued obsession with the finished product requires no explanation in a market-driven world, but the illumination of the creative process is still an important area of research, especially in light of the dramatic changes that have occurred in art in the past fifty years. The materials are frequently new and different, the issues have