Central bankers are scrambling to make sense of digital forms of money. An official from the Bank of Japan declared last week to Reuters that cryptocurrency won’t replace physical money any time soon. He may be right, but that’s a different tune from the one government bankers from some other countries have been singing. The deputy governor of China’s central bank, for example, said late last year that “conditions are ripe for digital currencies.” (We also reported on Japan’s interest in a currency it was calling J-Coin earlier this year.)

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So which is it? The truth is that every country is different, and the situation is often not so simple. In Sweden, for example, hardly anyone is using cash anymore, so the question is not whether digital money will replace physical money, but who will be responsible for supplying the digital money (for more: “Governments Are Testing Their Own Cryptocurrencies”). China’s government is probably interested in developing a cryptocurrency in part because this would give it more oversight over financial transactions (for more: “China’s Central Bank Has Begun Cautiously Testing a Digital Currency”).

Even if they decide not to issue their own coins, central banks are going to have to find a way to reckon with the broader cryptocurrency world. The market is still relatively small compared with the amount of money that flows through big government banks, but it’s growing fast. According to Reuters, some central bankers fear that if they do nothing, they could be blamed when it eventually crashes. Another concern is that a big shift to cryptocurrency would upend monetary policy. “It would change the banking system too drastically,” said the official from the Bank of Japan. But disruption appears to be coming, whether or not central bankers are ready for it.