NISS stands for Namibia Inter-bank Settlement System. It is owned and operated by the Bank of Namibia since implementation on 10 June 2002. The system is a Real Time Gross Settlement System (RTGS), which process and settles time critical payments under the principle of finality and irrevocability. This means that a transaction settled in NISS cannot be unwound after having been settled across the books of the participants in NISS at the Bank of Namibia. In Namibia the NISS system also settles cleared retail payment transactions from Namclear (Pty) Limited since 2004. These transactions include electronic fund transfer (EFT), cheque and card.