Lithuania's defense system is based on the concept of "total and unconditional defense" mandated by Lithuania's national security strategy. The goal of Lithuania's defense policy is to prepare its society for general defense and to integrate Lithuania into Western security and defense structures. The defense ministry is responsible for combat forces, search/rescue, and intelligence operations. The core of the Lithuanian force structure is the "Iron Wolf" Rapid Reaction Brigade consisting of three mechanized and motorized battalions and appropriate combat support elements. An additional three battalions are located in the western military district. The National Volunteer Defense Forces (home guard) consist of one battalion-sized unit in each of Lithuania's 10 districts.

The 600-man navy uses patrol boats and former Russian corvettes for coastal surveillance; the 800-man air force operates 10 helicopters and 17 planes used mostly for reconnaissance and border patrol. A mandatory 1-year conscription and alternative service is available for conscientious objectors. Over the next decade Lithuania's military will undergo a transformation, cutting its active reserve to 5,000 and number of conscripts to 2000. With its security guaranteed through NATO, Lithuania is creating a military that focuses more on contributing to international operations, rather than territorial defense. Its military has participated in 11 international operations, including Afghanistan and Iraq.

The 5,400 border guards fall under the Interior Ministry's supervision and are responsible for border protection, passport and customs duties, and share responsibility with the navy for smuggling/drug trafficking interdiction. A special security department handles VIP protection and communications security.