King Philippe succeeded to the throne in July 2013 on the abdication of his father, the 79-year-old Albert II, who stepped down on grounds of health.
Born in 1960, the future King Philippe graduated from the Belgian Royal Military Academy and went on to study political science at Oxford and Stanford.
He is a trained fighter pilot and paratrooper, and was widely expected to pass over his father and succeed to the throne on the death of his uncle Baudouin in 1993. But his apparent diffidence in public led to his father becoming king after all.
Prince Philippe became Duke of Brabant and went on to marry Belgian aristocrat Mathilde d'Udekem d'Acoz. They have four children, the eldest of whom, Princess Elisabeth, is heir to the throne.
As Duke of Brabant he served as honorary head of the Belgium's Foreign Trade Agency, and flew the flag for Belgian business on dozens of high-level trade missions worldwide.
Respect for the monarchy is one of the few factors that crosses the communal divide in Belgium, and King Albert exercised his constitutional authority in advising political leaders on the formation of a government during the 2010-2011 parliamentary stalemate.
King Philippe, on the other hand, is expected to have a difficult relationship with the hardline Flemish nationalists of the Vlaams Belang, whom he has publicly criticized.
Caretaker Prime Minister: Elio di Rupo
Elio di Rupo submitted his resignation following parliamentary elections in May 2014 but has been asked to remain in a caretaker capacity until a new government is formed.
French-speaking Socialist Mr di Rupo was appointed to lead a six-party coalition in December 2011, finally giving Belgium a government after a record year-and-a-half of tortuous negotiations.
Elio di Rupo
Mr di Rupo's appointment ended a record-breaking 541 days of political deadlock
His swearing-in put an end the country's longest political crisis, which had left Belgium increasingly under pressure from the financial markets. Only 10 days before the cabinet was formed, the Standard & Poor's rating agency cut Belgium's credit score.
The 541 days without a government came after elections - called when the previous government of centre-right Prime Minister Yves Leterme collapsed over a constitutional dispute - failed to produce a clear winner.
The New Flemish Alliance (NVA), which calls for even greater autonomy for Flanders, emerged as the largest single grouping from the vote, although the French and Flemish Socialists together had more seats overall. The NVA also became the largest party in Flanders at local elections in October 2012.
The dispute over francophone rights in Dutch-speaking areas near Brussels that led to the fall of Mr Leterme's government was also one of the main sticking points that protracted the formation of the new government.
Coming to power nearly half-way through its four-year term, the new coalition faced the daunting task of pushing through an extensive programme of constitutional reform as well as an austerity bugdet that included $15.2bn dollars of savings.French-speaking Socialist
The flamboyant Mr Di Rupo will be Belgium's first French speaking prime minister for more than 30 years, and Europe's second openly gay government leader after Iceland's PM, Johanna Sigurdardottir.
He faced suspicion from more right-leaning Flemish voters at being led by a French-speaking Socialist, and has been frequently lampooned for his poor Dutch.
Born in 1951 the son of poor Italian immigrants, his ascent to power has been portrayed as a rags-to-riches story.
A trained chemist, Mr Di Rupo started his political career in the 1980s. He became mayor of the city of Mons in 1982.
After serving in several other posts, he became Socialist Party leader in 1999, and was briefly prime minister (minister-president) of the largely French-speaking southern Walloon region of Belgium in 1999-2000 and 2005-7.
Belgium's current political instability was already evident under Mr Di Rupo's predecessor, Yves Leterme, who held the prime ministerial office twice and offered his resignation three times in the three years since the previous general election of July 2007.
Mr Leterme made little headway on the vital issue of devolving more powers to Belgium's regions, and his premiership saw frequent flare-ups of tensions between the French- and Dutch-speaking communities.