How Archives Work: Finding Aids, Reading Rooms and Research Tips

How archives organize records by creator, how to read a finding aid, and what to expect when you request boxes and visit a reading room.

Muninn · Last reviewed October 24, 2026 · 6 min read

The first visit to an archive surprises most people. There are no open shelves to browse. You fill out a form, hand over your bag, and wait while someone brings out a gray box. Inside are folders of letters or ledgers that may never have been published, and may not exist anywhere else.

Archives work differently from libraries for good reasons, and once you understand those reasons the system becomes much easier to use. This guide explains how archives organize their holdings, how to find what you need, and what to expect in a reading room, using guidance from the Society of American Archivists (SAA) and the U.S. National Archives.

How archives differ from libraries

The SAA's guide "Using Archives" puts the difference simply. Libraries mostly hold published materials that exist in many copies. Archives can hold published and unpublished materials in any format, including manuscripts, letters, photographs, sound and moving images, diaries, artwork and their digital equivalents, and these materials are often unique.

That uniqueness drives everything else. The SAA offers a clear example: when a library book wears out from use, the library buys another copy. A historic figure's handwritten diary would suffer the same wear, "but the diary is irreplaceable." Archival rules exist to protect the materials from damage and theft so they remain available to future researchers.

Archives also rarely keep everything. The National Archives says that of all the documents and materials created in the course of federal government business, only 1 to 3 percent are judged important enough for legal or historical reasons to be kept forever.

Why records are kept together: provenance and original order

Libraries arrange books by subject. Archives usually do not. They arrange records according to who created them, a principle called provenance. The SAA Dictionary of Archives Terminology describes provenance as a fundamental principle of archives, referring to the person, family or organization that created or received the items in a collection, and it explains that records of different origins are kept separate "to preserve their context."

A related principle, original order, asks archivists to keep records in the sequence their creator used. The idea is that the arrangement itself is evidence: a letter filed with a company's legal papers tells you something different from the same letter filed with personal correspondence.

For researchers, the practical lesson is to think about creators, not just topics. Imagine you are researching a small-town post office in the 1890s. Rather than searching only for the town's name, ask which agencies, businesses and families would have created records about it, and then look for their collections. At the National Archives, federal records are grouped into numbered record groups, which the SAA dictionary defines as collections of records that share the same provenance or were created by the same administrative unit.

Finding aids: your map to a collection

Because collections are arranged by creator, you need a guide to what is inside. That guide is the finding aid. The SAA's research guide describes a finding aid, sometimes called an inventory, register or calendar, as a document describing the contents of a collection, much like a table of contents for a book.

A good finding aid usually tells you:

who created the collection and how the archive acquired it
the date range and size of the material
how the material is arranged, often in series
a list of boxes and folders, with brief descriptions

Read the background sections, not just the box list. They often explain gaps, such as material that was lost, destroyed or held elsewhere.

Finding the right archive

The SAA suggests several starting points: check the bibliographies and notes of books on your topic to see which archives other researchers used; ask a reference librarian about WorldCat, which includes listings for archival materials; and search the websites and catalogs of likely repositories, including the National Archives Catalog for federal records.

Digitized collections are a great place to begin, but the SAA cautions that digital collections "often reflect just a fraction of the total holdings of a repository." Much of what you need may exist only on paper.

Do not skip the staff. The SAA calls contacting an archivist one of the most important ways to evaluate an archive's holdings. Write a short, specific message: describe your project, list the finding aids or collections you have already looked at, and ask whether they would recommend anything else.

Planning a visit

The SAA's planning advice includes several points that save real time:

Tell staff in advance which dates you will visit and which materials you want. Many archives store material off-site, and retrieval can take hours or days.
Confirm hours, and ask whether services are limited during evenings or weekends.
Ask about limits on how many boxes or folders you can request at once.
Check the reproduction policy and fees for photocopies, scans and personal photography.
Build in extra time. Deciphering hard-to-read handwriting takes longer than you expect; see our guide to reading old handwriting.

In the reading room

Rules vary, so always check the specific repository. The SAA lists common practices and the reasons for them: registering with identification; leaving coats and bags in lockers; no food, drink or gum; pencils only, because pencil marks can be erased; and request forms that track exactly what each researcher used.

Gloves are less common than people expect. The SAA notes that clean hands free of lotion are usually sufficient, though gloves may be needed for photographs and objects. Many archives allow cameras and laptops, with restrictions.

The National Archives' own research room rules are a concrete example. A researcher identification card is required to use archival materials at its facilities; you apply in person with a valid government-issued photo ID, and the card is valid for one year. Researchers must wear gloves on both hands when handling photographic materials that are not in protective sleeves, as well as slides and film, and must use nitrile gloves supplied by the agency rather than their own. Pencils and approved note paper are provided free.

Above all, keep folders and items in the order you received them. The SAA explains that misfiling can make staff think items are missing and inconveniences everyone who comes after you.

If you cannot travel

Not every project needs a visit. The SAA suggests asking whether the archive provides scans or photocopies, whether a research assistant can work on your behalf, and whether staff can answer a brief factual question by checking the material themselves. Original documents are rarely lent out, though some archives lend microfilm or printed material.

Whatever route you take, record a full citation for everything you use: the archive, collection, box and folder. You will need it to cite your work, and to find the item again.

Key takeaways

Archives hold unique, often unpublished material, so their rules are designed to protect it.
Records are organized by who created them (provenance), not by subject; search for creators.
Finding aids are the map to a collection; read their background notes as well as the box lists.
Contact staff early, and plan for off-site retrieval and request limits.
Keep materials in order and record box and folder details for every item you use.

Sources

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