At an official ceremony Bulgaria joined the NATO Cooperative Cyber Defense Center of Excellence located in Tallinn, Estonia. The Centre was established in 2008. It received full accreditation by NATO and attained the status of international military organization. Bulgaria is the 25^th member of NATO CCD COE. The organization supports the NATO members with expertise in various fields: cyber defense, technologies, strategies, operations and law. The center is the biggest department among 25 other similar structures within NATO. Japan, Montenegro, Croatia, Slovenia and Switzerland are currently negotiating to join the NATO Cooperative Cyber Defense Center of Excellence and Luxembourg and Australia voiced willingness to start accession negotiations.