In December 1999, a Framework agreement was signed between BAS and the Ministry of Defense, which became an important incentive to activate and strengthen cooperation in the field of research and technologies for national security and defense. Marking the first time in 10 years, thanks to this agreement, scientists and specialists from the BAS participated in various projects and scientific events (seminars, symposiums) in the field of research and technology for defense.

Between 2000 and 2002 more than 30 projects were developed in different directions (informatics, sensors and systems, energy sources, etc.). The first joint international projects were also conducted through a contract between the Ministries of Defense of the Kingdom of the Netherlands and the Republic of Bulgaria. The main contractors were institutes from BAS and the Netherlands Organization for Applied Research (TNO-Defense).