This paper aims to offer a functionality requirements set for metadata system based on the research of metadata system specifications at the National digital Archives program (NDAP) in Taiwan. Eight projects of the NDAP are chosen as case study to examine the functional requirements of metadata systems across museums, archives and herbarium communities. The study concludes five findings and proposes two recommendations including: 1.the suggestions for content experts, metadata managers and system designers to express and enhance the metadata request; and 2.the functionalities of metadata systems to support the NDAP.