Japan profile - leaders
Head of State: Emperor Akihito
Akihito succeeded his father, Hirohito, in 1989.
Under the 1947 constitution, Japan's emperors have a purely ceremonial role.
Prime minister: Shinzo Abe
Shinzo Abe swept into office with a landslide win for his Liberal Democratic Party (LDP) in 2012, having campaigned on a programme of tough action to pull Japan out of long economic stagnation.
His signature economic strategy - known as "Abenomics" - is a three-pronged approach of monetary easing, fiscal stimulus, and growth-oriented reform.
Implementation of the first two elements in Mr Abe's first term brought about a brief spurt of growth, but Japan slipped briefly back into recession in mid-2014, prompting Mr Abe to trigger new polls that he won emphatically.
Known for his hawkish foreign policy views, Mr Abe has removed the pacifist constitution's restrictions on foreign military deployment and authorized troops to fight abroad in certain circumstances.
He also called for a greater sense of national pride and backed a law requiring the teaching of patriotism in schools.
His nationalist views have caused tension with China and South Korea, in particular his 2013 visit to the Yasukuni shrine - seen by Japan's neighbours as a symbol of the country's militarism before and during World War II.
Mr Abe previously served a brief term as premier in 2006-7, when he was Japan's youngest leader since World War II, but stepped down early, citing ill health, after a series of scandals and gaffes sent support for his administration plummeting.
Mr Abe comes from a high-profile political family. His father was a foreign minister, while his grandfather, Prime Minister Nobusuke Kishi, was arrested as a suspected war criminal after the Second World War, but never charged.
His second stint as prime minister comes after four years in which the Democratic Party (DPJ) interrupted the LDP's longstanding dominance of politics on promises of curbing the influence of the powerful bureaucracy and interest groups
The often disunited DPJ government lost popularity as a result of unpopular efforts to deal with mounting public debt, criticism of its handling of the March 2011 tsunami, and a series of scandals.