| A | Welch
|
| B | Welch Associates: Gilman |
| A | Academies and Institutes |
| B | Associations, Organizations and Societies |
| C | Foundations |
| D | Federal Agencies |
| E | State Agencies |
| F | City Agencies |
| G | Educational Institutions |
| H | Hospitals |
| I | Corporations |
| J | Foreign Governments |
| A | Family Correspondence |
| B | Family items |
| A | Financial records |
| B | Diaries |
| C | Desk Calendars |
| D | Memorabilia: lists and memos |
| E | Birthdays |
| F | Formal invitations, programs |
| G | Miscellaneous data kept by Welch |
| H | Press clippings kept by Welch |
| A | Johns Hopkins University |
| B | School of Medicine |
| C | School of Hygiene and Public Health |
| D | Johns Hopkins Hospital, Wilmer Institute, and School of Nursing |
| E | Johns Hopkins Institute History of Medicine, Welch Library |
| A | Scientific |
| B | Historical/Philosophical |
| A | Notes |
| B | Notebooks, including laboratory notebooks |
| A | China and Japan |
| B | Europe |
| C | Travel Guides, postcards |
| D | Maps |
| A | Antivivisection |
| B | Public health in Britain |
| C | History of Medicine |
| A | Papers by Welch |
| B | Papers about Welch |
| C | Reprints collected by Welch at Huntington Library |
| D | Reprints by associates, contemporaries |
| A | Condolence letters, obituaries |
| B | Biographical correspondence with Flexner for biography |
| C | Biographical information on associates, contemporaries of Welch |
| D | Biographical material on Welch: Flexner's lists, index cards, clippings, other memorabilia |
| E | Late posthumous tributes, including 1950 centennial celebration |