Heads of state and government of the 26 NATO members will meet in Bucharest, Romania, for a summit from Wednesday to Friday.
The summit, the 23rd since the alliance's establishment, is of great importance as its agenda includes some very sensitive issues, to be discussed by the North Atlantic Council, NATO's top decision-making body.
It will also be the biggest summit of the alliance due to the number of its partners and other international organizations expected to be present, such as the Euro-Atlantic Partnership Council, the NATO-Russia Council and the NATO-Ukraine Commission.
In this context, meetings with NATO partners will be an integral part of the summit.
Moreover, Afghan President Hamid Karzai, UN Secretary General Ban Ki-moon and European Commission President Jose Manuel Barroso are invited to a high-level meeting on Afghanistan.
The summit will tackle hot issues that require quick and adequate resolution, such as the situation in Afghanistan and Kosovo and NATO's operations in other regions of the world.
NATO leaders will decide on whether to invite Albania, Croatia and Macedonia to join the alliance.
The stage is also set for debate among the allies over whether to grant Ukraine and Georgia's the NATO membership action plan, a step closer to membership, due to Russia's strong opposition.
During a meeting of the NATO-Russia Council, to be attended by the outgoing Russian President Vladimir Putin, the two sides are expected to discuss energy security and a missile defense shield the United States intends to install in the Czech Republic and Poland.
The sustainability of NATO's operations and its ability to confront security threats in an effective and unified way will also constitute major items on the summit's agenda.
The leaders will review NATO's capacity to provide forces for operations and examine ways and means of preparing for future security challenges.
The need for a new vision for the alliance might be put on the table at the summit, with proposals on a new military strategy and a revision of its decision-making process.