The One-To-One Principle: Challenges in Current Practice

The DCMI One-to-One Principle holds that related but conceptually different entities, such as a photograph and a digital image of that photograph, should be represented by separate metadata records. In practice, however, large numbers of practitioners do not adhere to this principle and commonly mix elements representing two related entities in a single metadata record. This paper explores reasons why this is the case, why it is problematic, how the principle itself would benefit from greater clarity, some practical options for maintaining the principle in current systems, with advantages and disadvantages of each, and suggests a possible compromise option. The paper focuses on the widespread application context of small to medium-sized cultural heritage institutions digitizing unique local resources, creating metadata using digital collection software packages such as CONTENTdm, and exposing only simple Dublin Core metadata for OAI harvesting and aggregating.