Correspondence is arranged alphabetically, with two sub-groups for each letter of the alphabet.    The first group (as:  Aa-Az, foldered) includes folders that contain multiple pieces of correspondence from only one name or title.  The second group (as: A's, other) includes folders containing only one or two pieces of correspondence from several names.   It may be necessary to search both sub-groups to find correspondence for a specific name.

To preserve the original order of the Muggeridge correspondence, some files carry the the titles Malcolm gave them, rather than the names of the actual correspondents they contain, for example: "About Kingsmill" and “Artist's Letters.”