Invoice management is often equated with storing invoices, and storage is the part everybody already has. Managing an invoice means holding everything that happened to it and being able to answer questions about it later: when it arrived, what it was checked against, why it stalled, who approved it, what was paid and against which version.
Arrival and identity
The date it reached the organisation and through which channel, which supplier sent it, and whether this supplier and invoice number have been seen before. These facts settle payment terms, duplicate detection and most supplier queries, and they cost nothing to record at the time and a great deal to reconstruct later.
What happened to it
What it was matched against and the result. Why it failed if it did, and who resolved it. Who approved it, when, and for how much. What it was coded to. This is the part produced once by a person and usually discarded, and it is exactly the part somebody asks about months later during an audit or a dispute.
Versions and closure
Suppliers reissue and correct invoices, and credit notes change what is owed. A resubmitted document is a new version rather than a new invoice, and keeping versions with their dates answers which one was paid against. Closing an invoice explicitly keeps the open list trustworthy, and a trusted list is one people actually use.
Questions people ask about what is invoice management
Is this what accounting software does?
Accounting software records the accepted transaction. Invoice management covers the stretch before that, when the invoice exists but is not yet a transaction.
How long should the history be kept?
As long as the invoice itself, according to your own retention obligations. The approval trail is part of the record of the transaction.
Does it include payment?
Up to and including recording which invoices a payment settled, which is what makes reconciliation and supplier queries straightforward.