President: Janos Ader
A lawyer and member of the European Parliament for Hungary's governing Fidesz party, Janos Ader was elected President of Hungary in 2012 in a parliamentary vote that was boycotted by the main opposition Socialist Party. The far-right Jobbik party voted against him, but the large Fidesz majority guaranteed his win.
Mr Ader took over from Pal Schmitt, another Fidesz loyalist who was forced to resign after a Hungarian magazine revealed that his 1992 doctoral thesis was extensively plagiarised.
The new president, born in 1959, was a co-founder of Fidesz and took part in the talks that brought an end to Communist rule. He served as an MP in 1990-2009 and was speaker of parliament in 1998-2002.
Mr Ader has pledged to make full use of his powers, which some Hungarian commentators have taken to mean that he will scrutinise proposed laws more carefully than did his predecessor.
He is nonetheless closely associated with the controversial policies of Prime Minister Viktor Orban, and helped draft changes to election laws and the role of the judiciary that prompted complaints from the European Commission.
Prime minister: Viktor Orban
Mr Orban scored his third election victory in April 2014, when the coalition led by his conservative Fidesz party gained more than 44% of the vote, giving it an 18% lead over the Socialist-led opposition alliance.
He first served as prime minister from 1998 to 2002, then had an eight-year spell in opposition before reclaiming the premiership after the Fidesz-led coalition won a triumphant two-thirds majority in the April 2010 parliamentary election.
Fidesz's landslide election victory in 2010 allowed it to push through a number of radical changes.
The new government inherited an economy in deep crisis, which it pledged to tackle by cutting taxes, curbing tax evasion, creating jobs and reducing state bureaucracy.
One of Mr Orban's first steps was to slash the number of ministries to eight. His government subsequently reduced the number of MPs from 386 to 199 and introduced a new electoral law under which elections consist of a single round instead of two.
The biggest challenge faced by the Fidesz government elected in 2010 was Hungary's severe public debt problem, which it tackled with what the government itself described as an "unorthodox" economic policy.
This policy included high taxes on banks and multinationals - including heavy windfall taxes on mostly foreign-owned energy companies - and the nationalisation of private pension funds.
Such radical revenue-raising measures allowed the government to introduce a series of voter-pleasing policies, notably big utility price cuts for households, which are thought by many analysts to have played a key part in Fidesz's re-election in 2014.
Many were implemented in defiance of the international financial institutions and what Mr Orban likes to refer to as the "Brussels bureaucrats".
Mr Orban was able to turn this outside criticism to his advantage by appealing to nationalist sentiment and playing to an element in the national psyche that sees Hungarians as engaged in a perpetual struggle against foreign domination.
With the far-right Jobbik party seeing a boost in its support in recent years, the government has been accused of failing to adequately address the issue of hate speech, especially after some prominent Jobbik figures made inflammatory anti-Roma and anti-Jewish comments.
However, Mr Orban insists that his more moderate stance represents a bulwark of democracy against extremism, and his tough approach to law and order - a flagship Jobbik issue - appears to have prevented the more conservative Fidesz supporters from drifting further to the right.Democratic concerns
A media law introduced in January 2011 was widely criticised at home and abroad for undermining media freedoms. The EU said that amendments to the media law passed in May 2012 failed to address concerns over the political independence of Hungary's Media Authority, and it called on the Hungarian government to do more to ensure media pluralism.
At the beginning of 2012, Mr Orban's government introduced a new constitution to replace the one drafted in 1989, when Hungary was emerging from 40 years of communist rule.
Mr Orban insisted that a new constitution was necessary in order to complete the work of eradicating the legacy of communism, but critics pointed out that some of the checks and balances essential for the healthy functioning of a democracy had been removed, and that the changes curtailed civil liberties, harmed free speech and cemented Fidesz's hold on power.
Mr Orban rejects such charges, insisting that Hungary's unique character and history mean that the nature of Hungarian democracy is necessarily different from that in other countries.
However, a key speech he gave in July 2014, in which he said that liberal democracy has had its day and that some "illiberal" states such as Russia and China provide Hungary with more appropriate models, did little to allay the concerns of his critics.
Since then, Mr Orban's efforts to forge a special relationship with Russian President Vladimir Putin - despite the disapproval of Hungary's allies in the EU and Nato - have seriously dented his popularity at home.
Mr Orban maintains that Hungary needs to cultivate friendly relations with Russia in order to ensure its energy security, but many Hungarians have unhappy memories of the period when their country was a Soviet satellite state and have serious reservations over this aspect of the leadership's foreign policy.
Fidesz approval ratings began to fall steeply during the second half of 2014, and Mr Orban suffered a major setback in February 2015 when his party lost a key by-election in what had previously been a safe Fidesz seat and at the same time lost its two-thirds majority in parliament for the first time in five years.