In late 1997, Academic Press will launch the Image Directory, an online union catalog of information about art images. Based on descriptions provided by museums and image owners all over the world, the Image Directory will be an ever-growing union catalog which will provide item-level and collection-level access to data and low-resolution images. The project isanalogous to Books in Print in that it collects data from many sources and places them in a uniform format, thus facilitating search strategies and promoting standardized descriptive vocabularies. There is nothing novel about the concept: Books in Print began shortly after World War II, building upon a book cataloging tradition that extends backward to hundreds ofyears. What distinguishes the Image Directory-the reasons a union catalog of art images has been impossible to create until now-is inextricably tied to the rise of electronic publishing and changes within the museum community.