"The three Baltic states left the ruble system shortly after independence, with both Estonia and Lithuania opting for a currency board system -- the former pegging its kroon to the DM, but the latter linked the litas to USD. After a brief period with a temporary currency, the Latvian ruble, Latvia returned to the lats in 1993 and eventually defined it in terms of the SDR. As all three countries have applied to EU membership, a number of political and technical issues need to be resolved before their incorporation in the EMU."