The role of central banks and governments in regulating the financial system A Central Bank is an institution that manages a state's currency, monetary supply and interest rates. They also usually oversee the commercial banking system within the state. The UK's central bank is the Bank of England and the US' is the Federal Reserve. The main functions of a Central Bank: Monetary policy . Central banks usually implement this by raising/lowering the base interest rate for example. Acting as a banker to the government - so carrying out exchange, remittance, etc. on behalf of the government. Acting as a banker for other banks - the central bank will often supervise commercial banks and will act as a 'lender of last resort' to them. Regulating the financial system - will regulate the system to ensure stability. Liquidity Liquidity is how easily assets can be traded. Cash is the greatest liquidity as it can be immediately traded for any good.