How many countries joined NATO:

A) 20

B) 26

C) 32

D) 34

As of today, July 10, 2024, there are currently D) 32 countries that have joined NATO.

NATO was created by 12 countries from Europe and North America on 4 April 1949.
Since then, 20 more countries have joined NATO through 10 rounds of enlargement (in 1952, 1955, 1982, 1999, 2004, 2009, 2017, 2020, 2023 and 2024).
Article 10 of the North Atlantic Treaty sets out how countries can join the Alliance. It states that membership is open to any “European State in a position to further the principles of this Treaty and to contribute to the security of the North Atlantic area”.
Any decision to invite a country to join the Alliance is taken by the North Atlantic Council, NATO’s principal political decision-making body, on the basis of consensus among all Allies.

2009
Albania