ENSince the inception of NATO, one of the key political issues among the Allies has been burden-sharing, which can be defined as the “distribution of costs and risks among members of a group in the process of accomplishing a common goal”. The United States, as the biggest economic and military power in the Alliance, has always tried to ensure that European countries take on their fair share of the overall burden for maintaining the collective security system. Meanwhile, the Europeans usually have been quite reluctant to uphold their commitments; their burden-sharing behaviour has even been labelled as “the art of manipulating alliance relationships for political gain”. The problem can be traced back to 1949 when the US Secretary of State Dean Acheson, while discussing the ratification of the Washington Treaty, emphasized the need to “ensure that nobody is getting a meal ticket from anybody else so far as their capacity to resist is concerned”. Disagreements about burden-sharing were recently fuelled again by a substantial economic crisis that started in 2008. As a result of the austere economic environment, nations have drastically cut their defence budgets. For example, between 2008 and 2012 such Allies as Greece, Latvia and Bulgaria reduced their defence spending by 44 %, 54 % and 37 %, respectively. This certainly affects their level of ambition and highly restricts their ability to participate in NATO operations, as well as their capability to develop programmes. As warned by NATO Secretary General Anders Fogh Rasmussen, “unless we Europeans take our security seriously, North Americans will rightly ask why they should. Unless we recommit to our own defense, we risk seeing America disengage - and Europe and America drift apart”.This problem is particularly relevant for the smaller members of NATO which often are not capable, and more importantly, even not willing to contribute proportionally. This is a paradox because the very fundamental interests of small states require a reliance on external security guarantees as the best option for ensuring their national security. In other words, as a result of their military and economic vulnerability, the security of small states can be guaranteed mainly through effective alliance membership rather than building national military capabilities. These trends have been well illustrated by Lithuanian defence policy since the country became a member of NATO. Lithuania has officially stated that its national security is a constituent part of the indivisible security policy of NATO and the European Union. Collective deterrence ensured by NATO is the main principle of the defence strategy of Lithuania. The reliance on NATO’s Article 5 of the Washington Treaty assurances became the modus operandi of developing Lithuania’s national defence capacity.