March 1990 - Representatives of the North Atlantic Assembly headed by the institutionґs President Patrick Duffy visit Bulgaria.
July 1990 - Diplomatic relations with the Alliance are established.

November 1990 - Bulgarian Foreign Minister Lyuben Gotsev visits NATO Headquarters in Brussels and meets Secretary General Manfred Wцrner and permanent representatives from the NATO sixteen member states.

June 1991 - Secretary General Manfred Wцrner pays the first visit to Bulgaria.

November 1991 - Bulgarian President Zhelyu Zhelev visits Brussels; in a speech made at NATO Headquarters he said that his country relies on the North Atlantic Pact where its security is concerned and that it would like to sometime enter the Alliance.

April 1993 - NATO Supreme Allied Commander Europe John Shalikashvili visits Bulgaria.

December 1993 - Bulgarian Parliament unanimously says that Bulgaria is seeking the quickest possible admission to NATO and the Western European Union (WEU).

January 1994 - The Partnership for Peace project is approved and a new security policy is defined at the summit in Brussels.

- The Bulgarian Foreign Ministry confirms that Bulgaria is interested in the Partnership for Peace initiative.

February 1994 - Bulgarian President Zhelyu Zhelev signs Bulgariaґs accession to the Partnership for Peace project at NATO Headquarters in Brussels.

- The chairman of the North Atlantic Assembly, a NATO parliamentary body, Karsten Voigt, visits Bulgaria.

May 1996 - NATO Secretary General Javier Solana visits Bulgaria.

January 1997 - Bulgarian President Petar Stoyanov urgently calls for his country to be admitted among NATO membership candidates at NATO Headquarters in Brussels.

February 1997 - The Bulgarian provisional government approves a declaration in which it expresses the wish for Bulgaria to become a fully-fledged member of NATO (the first such announcement made by the Bulgarian government).

March 1997 - The Bulgarian government approves a programme of incorporation of the country into NATO.

October 1997 - The 43rd General Assembly of the Atlantic Treaty Association (ATA) in Sofia (held for the first time outside the NATO member countries); the meeting is participated in by 741 representatives from 50 states and five international organisations.

April 1998 - NATO Secretary General Javier Solana visits Sofia; the NATO information centre opens in Sofia.

July 1998 - Bulgarian President Petar Stoyanov in a meeting with NATO Secretary General Javier Solana in Brussels asks for his countryґs quick admission in the Alliance; he justifies this among others by the Kosovo conflict.

October 1998 - The National Security Council of the Bulgarian Republic decides (October 10) that Bulgaria will comply with the NATO request and will make its air space available for a possible action against Yugoslavia; the request is approved by parliament on October 23.

February 1999 - the government announces (February 18) that in case of a NAT0 military operation in Kosovo it will cooperate with the Alliance, but will not directly participate in military actions; the government approves (February 25) a draft framework agreement with NATO which would make it possible to transport via Bulgarian territory supplies and building material to NATO peace-keeping units as well as to the members of the units in case of their deployment in Kosovo.

March 1999 - Bulgarian Parliament approves (March 25) a statement in which it expressed solidarity of Bulgaria with the NATO effort to prevent a "deepening and extension" of the Kosovo crisis.

- The territory of Bulgaria is hit by two NATO air to air missiles; nobody is wounded in the explosion and no material damage is inflicted.

April 1999 - NATO holds its summit in Washington; Slovakia, Bulgaria, Romania, Slovenia, Lithuania, Latvia and Estonia are among the countries mentioned within enlargement discussion at the summit; NATO presents the Membership Action Plan (MAP) of Macedonia which forms the basis of the individual assessment of a candidate country.

- Parliament passes a military doctrine the central point of which is Bulgariaґs future entry into NATO (the first military programme after the fall of communism in the country).

- The North Atlantic Alliance asks (April 18) Bulgaria for a permission to use its air space.

- Parliament preliminarily consents to NATO flights over Bulgarian territory (April 19).

- The Constitutional Court supports the decision to open an air corridor over Bulgarian territory to NATO aircraft and the permission for foreign military units to cross Bulgarian territory (April 22).

May 1999 - The Bulgarian Constitutional Court rules that the agreement between Bulgaria and NATO which allows Alliance aircraft to fly over Bulgarian territory in connection with the operation against Yugoslavia does not violate the Constitution; 65 deputies from the post-communist Bulgarian Socialist Party and the Bulgarian Euro-left asked the court to review the agreement (May 3).

- Bulgarian Parliament, in second and last reading, passes an agreement meeting the request by the North Atlantic Alliance that its aircraft be allowed to fly over Bulgarian territory during the operation against Yugoslavia; the Alliance in exchange provided security guarantees to Bulgaria (May 4).

- Further missiles (seven altogether, the last one being Yugoslav) fall on Bulgarian territory.
June 1999 - NATO addresses a note to the Foreign Ministry in Sofia asking it for permission for Alliance units including weapons and further equipment to transit Bulgarian territory on their way to Kosovo within logistic support for international peace-keeping units (KFOR) from the Bulgarian side (June 18).

- The government decides to permit NATO units included in KFOR to cross Bulgarian territory (June 21).

- The transit is consented to by parliament.

July 1999 - Javier Solana visits Bulgaria.

September 1999 - Bulgariaґs direct loss inflicted by the Kosovo crisis amounts to leva168.7 million (EUR86.25 million ), indirect losses to leva16.3 million (EUR8.33 million), the Trade and Tourism Ministry announces.

January 2000 - An informal meeting in Plovdiv deals with the situation in the Balkans, it is attended by the premiers of six states which formerly were part of the former Yugoslavia or neighboured on it, and high representative for EU common foreign and security policy Javier Solana and NATO Deputy Secretary General Sergio Balanzino.

February 2000 - NATO Secretary General George Robertson visits Bulgaria.

March 2000 - NATO Supreme Allied Commander Europe General Wesley Clark visits Bulgaria.

May 2000 - Bulgarian political parties represented in parliament reach consensus on the countryґs NATO and EU entry; a resolution in support of the Bulgarian governmentґs effort in this respect is passed by a majority of 189 to 3 votes in the unicameral Peopleґs Assembly.

June 2000 - Supreme Allied Commander Europe General Joseph Ralston visits Bulgaria.

August 2000 - NATO compensates a Bulgarian family whose flat was destroyed by a stray missile of the Alliance during the air strikes against Yugoslavia; the compensation amounted to leva 67,253.

October 2000 - NATO Secretary General George Robertson visits Bulgaria.

March 2001 - Bulgaria and NATO sign (March 21) in Brussels an agreement allowing NATO to set up a temporary base on Bulgarian territory if needed.
April 2001 - Bulgarian Parliament ratifies (April 6) an agreement with NATO under which NATO may temporarily deploy its units on Bulgarian territory; the document was signed for five years.

October 2001 - The heads of ten post-communist countries seeking membership of the North Atlantic Alliance attend in Sofia a summit aimed to encourage NATO to invite them at the Prague summit in November 2002 to join the Alliance. In a joint communique they expressed support for the anti-terrorism campaign waged by the United States.

February 2002 - NATO Secretary General George Robertson and Bulgarian President Georgi Parvanov meet.

- NATO Secretary General George Robertson visits Bulgaria.

March 2002 - Ten central and east European countries seeking NATO membership meet in a conference in Bucharest.