In 2004, the Eurogroup of eurozone finance ministers decided to replace the rotating chairmanship with a permanent president.
Juncker was appointed as the first permanent president and assumed the chair on 1 January 2005.
He was re-appointed for a second term in September 2006.
Under the Lisbon Treaty, this system was formalised and Juncker was confirmed for another term.
Juncker stepped down on 21 January 2013, when he was succeeded by Dutch Finance Minister Jeroen Dijsselbloem.

During his period as "Mr. Euro", the group was instrumental in negotiating and supervising bailout packages for the countries that faced bankruptcy: Greece, Ireland, Portugal, Spain and Cyprus.

Juncker was also an outspoken proponent of enhanced internal co-operation and increased international representation of the group.

In a debate in 2011, during the height of the eurozone crisis, Juncker responded to a conference-goer's suggestion to increase the openness of the strategy discussions in the eurogroup, by stating: "When it becomes serious you have to lie".
Scholars of financial markets have remarked that the quote is often taken out of context by critics; best practice amongst monetary policy committees in most states is to keep negotiations on decisions confidential to prevent markets from betting against troubled countries until they are finalised.
This need is complicated by the Eurozone's arrangements, in which policy negotiations are held in high-profile international summits of eurozone finance ministers, where leaks of ongoing negotiations may potentially put "millions of people at risk".
Indeed, the quote continues;
Monetary policy is a serious issue.
We should discuss this in secret, in the Eurogroup.
 ... The same applies to economic and monetary policies in the Union.
If we indicate possible decisions, we are fuelling speculations on the financial markets and we are throwing in misery mainly the people we are trying to safeguard from this.
 ... I'm ready to be insulted as being insufficiently democratic, but I want to be serious, ... I am for secret, dark debates.

— Juncker, on the constraints to openness from market actors during the financial crisis, 20 April 2011.
This comment has been considered a quip.

He further stated that when asked by a journalist to comment on those meetings he had had to lie, making clear it went against his personal moral conviction as a Catholic.
In 2004, the Eurogroup of eurozone finance ministers decided to replace the rotating chairmanship with a permanent president. Juncker was appointed as the first permanent president and assumed the chair on 1 January 2005. He was re-appointed for a second term in September 2006. Under the Lisbon Treaty, this system was formalised and Juncker was confirmed for another term. Juncker stepped down on 21 January 2013, when he was succeeded by Dutch Finance Minister Jeroen Dijsselbloem.
During his period as "Mr. Euro", the group was instrumental in negotiating and supervising bailout packages for the countries that faced bankruptcy: Greece, Ireland, Portugal, Spain and Cyprus.
Juncker was also an outspoken proponent of enhanced internal co-operation and increased international representation of the group.
In a debate in 2011, during the height of the eurozone crisis, Juncker responded to a conference-goer's suggestion to increase the openness of the strategy discussions in the eurogroup, by stating: "When it becomes serious you have to lie". Scholars of financial markets have remarked that the quote is often taken out of context by critics; best practice amongst monetary policy committees in most states is to keep negotiations on decisions confidential to prevent markets from betting against troubled countries until they are finalised. This need is complicated by the Eurozone's arrangements, in which policy negotiations are held in high-profile international summits of eurozone finance ministers, where leaks of ongoing negotiations may potentially put "millions of people at risk". Indeed, the quote continues;
Monetary policy is a serious issue. We should discuss this in secret, in the Eurogroup. ... The same applies to economic and monetary policies in the Union. If we indicate possible decisions, we are fuelling speculations on the financial markets and we are throwing in misery mainly the people we are trying to safeguard from this. ... I'm ready to be insulted as being insufficiently democratic, but I want to be serious, ... I am for secret, dark debates.
— Juncker, on the constraints to openness from market actors during the financial crisis, 20 April 2011. This comment has been considered a quip.
He further stated that when asked by a journalist to comment on those meetings he had had to lie, making clear it went against his personal moral conviction as a Catholic.
Jean-Claude Juncker