American publishers of indecent books from 1840 to 1890 were not outsiders to the printing trades. They should be seen instead as entrepreneurs whose technological practices and business strategies were largely representative of the diversity within American publishing. Books prohibited or later destroyed because of their content survived in a relatively wide variety of forms in the hands of rare book collectors, making such artifacts perhaps even more important for the study of industrial practices than literary works collected in greater numbers by research institutions. Those rare artifacts make available long-lost details about the men and women who manufactured print at the boundaries of social propriety, the production technologies they employed, and the place of difficult-to-research publishers in the American book trades. Conservation, papermaking, illustrations, printing, and typefounding are as important to the history of American erotica as the more famous prosecutions led by Anthony Comstock. Focusing on works considered indecent by the nineteenth-century bibliographer Henry Spencer Ashbee, this dissertation integrates the political economy of print with an analysis of the material forms of semi-erotic and obscene books. Surviving artifacts offer evidence about regional production styles and the ways that fiber selection, and particularly the use of straw in low-quality papers, influenced the prevalence of yellow wrappers for ephemeral works. Printer skill levels and capitalization can sometimes be determined through the presence of gripper marks on printed sheets. Reconstructing and contextualizing the technological practices of these publishers can create new tools for bibliographical analysis, an accessible source of information about technical processes for general historians, and a wealth of data about publishers such as William Berry, whose role in networks of erotica in nineteenth-century America has only recently begun to be appreciated.