In the summer of 1989, major discoveries were made at the site of Joya de Ceren, El Salvador, where sudden depositions of volcanic ash in A.D. 600 resulted in unusually favorable conditions of preservation. The theoretical framework for the research is household archaeology, the study of prehistoric household groups. Household archaeology, as applied to Ceren, can take advantage of the extraordinary preservation to study households in terms of their key activities of (a) production, including food, implements, vessels, and structures; (b) pooling, including storage, distribution, maintenance, and curation activities; (c) transmission of knowledge and material goods including access to resources; (d) reproduction in both the biological and sociocultural senses; and (e) co-residence/membership in the functioning residential group. One of the major finds was a possible codex or Precolumbian manuscript.