In May 2012, due to the critical situation in Greece before the elections and given the established electoral law, Democratic Alliance decided to cooperate with New Democracy, based on a specific framework of values and to suspend its activities.

[1] Dora Bakoyannis rejoined New Democracy on 21 May 2012, ahead of the parliamentary election in June, where she headed the state deputies' ballot.

After the collapse of the junta, she returned to Greece and continued her academic studies in public law at the National and Kapodistrian University of Athens.

From December 1992, she served as Minister for Culture of Greece until the 1993 election, when she was re-elected a member of Parliament for New Democracy as the main opposition party.

In September 1997 she was appointed by New Democracy leader Kostas Karamanlis in the party's Department for Development and as Shadow Minister of Foreign Affairs and Defence in May 2000.

On 29 March 2002, Bakoyannis was picked to run for Mayor of Athens in the 2002 local elections, both a choice of Kostas Karamanlis who was looking for a way to demonstrate New Democracy's growing strength against the ruling Panhellenic Socialist Movement and a chance for Bakoyannis to earn prestige by this office in advance of the city hosting the Olympic games.

She was elected what was aired as Athens' first female mayor in the city's 3,500-year history,[6] defeating her socialist opponent Christos Papoutsis and receiving a percentage of 60.6% in the runoff.

During her incumbency, she promoted the cooperation in the Balkans, where Greek companies are heavily investing, traveled through the Middle East to help outline solutions to problems and attended meetings of the Organization for Security and Co-operation in Europe to discuss developments in the region.

[13] A member of the Greek delegation to the Parliamentary Assembly of the Council of Europe since 2012, Bakoyannis serves as chairwoman of the Sub-Committee on relations with the OECD and the EBRD.

In 2015, Bakoyannis was named a member of the OSCE Panel of Eminent Persons on European Security as a Common Project, chaired by Wolfgang Ischinger.

Her efforts to get Athens ready to host the 2004 Summer Olympics successfully, her actions to transform the city for the benefit of its residents and her fight against terrorism helped Bakoyannis win the award.

During the contest she was strongly supported by the Greek community and also received thousands of votes from several countries around Europe, North America and Australia.

[28] On December 13, 2002, two months after taking office as mayor of Athens, an assassination attempt was made on her by a perpetrator who was considered mentally disturbed.