accessions

Accessions is a term used across several fields to denote either the act of joining or adding something, or the item that has been added. Although the specifics vary by domain, common threads include formal inclusion, cataloging, and unique identification within a collection or system.

In international law, accession refers to the process by which a state becomes a party to a treaty. It typically occurs after a treaty is opened for signature or after it has entered into force, allowing states that did not sign to agree to be bound by its terms. Accession often carries the same legal effect as ratification, though procedures and timing may differ by treaty and jurisdiction.

In libraries, archives, and museums, an accession is both the act of formally accepting a new item into a collection and the item itself. The acquisition is recorded in an accession register, and the item is assigned an accession number to track provenance, custody, and subsequent handling. Accession records support inventory control, conservation, and research use.

In botany and germplasm collections, an accession denotes a specific sample of plant material collected from a source population and stored for future study or breeding. Each plant accession is given a unique accession number and associated data such as origin, collector, and collection date, enabling precise management and sharing of genetic resources.

In biological databases and sequencing repositories, an accession number uniquely identifies a record—such as a gene sequence or nucleotide entry—allowing researchers to retrieve and cite data unambiguously.

Overall, accessions function as formal mechanisms for integration, cataloging, and traceability across institutions and disciplines.