This case study examines the development of the OCLC Digital Archive, a third-party service that provides (1) tools for the capture of individual online resources and offline collections; (2) a repository in which those resources and collections can be stored for preservation purposes; and (3) an administration module, which allows depositors to manage their archived resources after submission.The OCLC Digital Archive complies with the Reference Model for an Open Archival Information System (OAIS). OAIS is a framework, implementations of which vary. The case study focuses on OCLC's development of requirements based on the OAIS and member input, highlighting factors that influenced our decisions.Several categories of factors influenced the three-year development project. These factors include the nature of OCLC, the institution developing the archive; the local depositor community; and the global digital archiving community. Implementation decisions affected include object types and formats accepted into the archive, access methods, preservation metadata creation, types of tools developed, rights management capabilities, and preservation planning.