Accession Number refers to the number that is assigned to each accession. Accessioning is the process of formally accepting objects into the organization's collection. All objects accepted into the collection from the same source at the same time are part of the same accession. The accession number identifies the objects as a group and links them to the information about how they were acquired by the organization. If you are creating an accession record, you must assign an Accession Number for each accession record. However, if you do not have accession information and you do not want to create an accession record, you can just enter your catalog records without assigning Accession Numbers.
Object ID refers to the unique number that is given to each individual object. For many institutions, this number would be synonymous with the catalog number. PastPerfect requires a unique Object ID number for every item that you add, whether through the accession record or directly to the catalog. The program will not allow you to enter a duplicate Object ID number, throughout any of the catalogs (Objects, Photos, Archives, and Library). In other words, Object ID numbers you use in one catalog cannot be repeated in a different catalog. It is possible to have multiple Object ID numbers for a single Accession Number. So, while the total number of Object IDs assigned is dependent upon how many items are contained in the accession, they would all share the same Accession Number.
PastPerfect does not assign numbers to your accessions or objects. Your institution must provide these numbers. PastPerfect is designed to handle any numbering system up to 15 characters for Accession Numbers and up to 25 characters for Object IDs. Characters may be letters, numbers, punctuation, or spaces.
Collection numbering systems vary greatly. One common system for numbering is the Trinomial System. In this system, the Accession Number would be the first two parts: the year followed by the accession group within that year. For instance, 2008.4 would mean that this is the 4th accession in 2008.
As previously mentioned, the Object ID number contains a third number, the object number, which is added to the end of the two-part Accession Number. So, to create an Object ID, one would just add the third part (the object number) onto the Accession Number. For example, 2008.4.1 would reference the first item in the 4th accession of 2008. Then, 2008.4.2 would be the second item in the 4th accession of 2008, and so on. Many find this numbering system helpful because you can easily recognize the accession to which an object belongs and the year it was accepted into the collection.
Changing one’s numbering system does occasionally happen, although it is not recommended and should be seriously evaluated before embarking on such a task. Consistency in numbering systems is the key to understanding them. If your institution should decide to change its system, it is important that you record the decision and date to keep in your files for future users to reference. Then, be consistent in your numbering from this point forward, both in PastPerfect and when labeling your items. It is not always necessary or recommended to renumber your entire collection.
There are many reference books that include information on numbering systems, accession numbers, and object ID numbers. Below are two books on current collections management standards that our staff uses frequently.
- Reibel, Daniel B. Registration Methods for the Small Museum. Third Edition. Walnut Creek, CA: Altamira Press, 1997.
- Buck, Rebecca A and Jean Allman Gilmore. The New Museum Registration Methods. Washington, DC: American Association of Museums, 1998.