An example: distinguish the matter from the individual letter
Imagine a case involving an initial enquiry and three replies. A case reference can connect the exchange, while a separate letter reference identifies each particular document. When someone calls about the second reply, an authorised colleague should be able to locate that exact item without confusing it with the latest letter in the case.
Discuss which references already exist in your organisation and which need to appear on a printed page. A customer reference, an internal case reference and a delivery-provider reference can all have useful roles, but their labels need to be clear. Do not overload one field with changing status information. If an external system creates a request, agree how its reference will be retained alongside the correspondence reference so that staff can trace the relationship in either direction.
Why an automatic reference matters
A unique reference helps people identify one exact correspondence record when titles are similar or a conversation has several versions. Rather than expecting users to invent numbering conventions, Epistles should allocate a stable, collision-resistant reference whenever an eligible letter is created or finalised. The reference can appear in the letter PDF, its record and relevant notifications, making support and internal discussions easier.
The public-facing reference should never act as a password. Knowing or guessing a number must not unlock confidential letters. Internal record identifiers, access authorisation and verification tokens are separate concerns. When a draft becomes final, its reference should remain consistent even if the owner later renames the subject or reorganises a folder.
Folders that reflect how real correspondence happens
People do not naturally organise their letters by file extension. They think about matters: an insurance claim, a tenancy, a client relationship or an exchange with a public authority. Dedicated correspondence folders should follow that mental model. Each folder can hold incoming letters, outgoing replies, attachments, notes and reminders, while a case record connects events that belong to the same issue.
Folders should stay simple for individuals and become more structured as organisations grow. A personal account might contain Home, Banking, Work and Insurance. A professional firm may organise by client, matter and department, with sensitive folders visible only to authorised colleagues. Moving a letter between folders must not alter its identity, final document or historical evidence.