This publication, the inaugural volume of Conservation Research, provides research by Andrew W. Mellon Fellows from 1984 to 1988 and by members of the conservation staff of the National Gallery of Art. Readers are introduced to analyses forming the basis for a greater understanding of Renaissance bronzes; techniques that produced obscure and charming medieval pasteprints; the myths and realities behind Gauguin’s choices of canvases and painting materials; characteristics of Japanese papers selected by Whistler; the painting methods of El Greco; and the impressionists’ attitudes toward varnish coatings on paintings.