Germany’s economy boomed in the first three months of this year; Spain’s decelerated sharply in the wake of global financial turmoil. Such stark differences might appear to create problems for the European Central Bank, custodian of the continent’s single currency.

Not so, according to one of the longest-serving members of the bank’s governing council. Vítor Constâncio, governor of Banco de Portugal, argues that divergences within the 15-country currency union reflect normal adjustment processes and are not a problem for eurozone policymakers.