Furnishing details of outward supplies requires electronic monthly reporting, recipient verification and time-limited rectification with commissioner extensions. Section 37 mandates electronic furnishing and recipient communication of details of outward supplies (including invoices, debit notes, credit notes and revised invoices) for each tax period; recipients must accept or reject communicated details within a prescribed response window, which amends the supplier's return. Suppliers must rectify errors in unmatched details, pay any tax and interest in the relevant return, and comply with a statutory cutoff for rectification tied to the September return following the financial year or the relevant annual return, subject to Commissioner-granted time extensions.