where are its headquarters located?
Evere, Brussels, Belgium
NATO
ATO's Headquarters are located in Evere, Brussels, Belgium, while the headquarters of Allied Command Operations is near Mons, Belgium.

what was the purpose of north atlantic treaty organization (nato) NATO constitutes a system of collective defence whereby its independent member states agree to mutual defence in response to an attack by any external party can you name some of its founding members? UNANSWERABLE which major event led to the foundation of this organisation? Korean War
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NATO [SEP] Introduction
The most recent member state to be added to NATO was North Macedonia on 27 March 2020. NATO currently recognizes Bosnia and Herzegovina, Georgia, and Ukraine as aspiring members. An additional 20 countries participate in NATO's Partnership for Peace program, with 15 other countries involved in institutionalized dialogue programs. The combined military spending of all NATO members constitutes over 70% of the global total. Members agreed that their aim is to reach or maintain the target defense spending of at least 2% of GDP by 2024.