What it is
The agreement behind AJP-3.20
STANAG 6514 commits NATO nations to implement AJP-3.20, Edition A, the Allied joint doctrine for cyberspace operations. The agreement itself runs to a handful of pages and holds no doctrine: it states an aim, names the publication, and sets out how a nation ratifies and implements it. Its aim is given as an interoperability requirement, "to provide an overarching framework for cyberspace operations, cyberspace operations principles and planning considerations, roles and responsibilities in joint operations, as well as relationship between cyberspace activities and the joint functions."
A STANAG is the instrument, not the content. Nations ratify it, implement it through their own regulations and procedures, and a company encounters it only because a contract or a tender invokes the doctrine it carries. Ratification and implementation are separate, a nation may ratify with reservations, and so the question "is STANAG 6514 mandatory" has a contractual answer and no general one.
Not an information security standard
This is the point worth stating first on a site like this one. AJP-3.20 is military doctrine: how NATO plans and conducts operations in and through cyberspace as a joint operational domain, alongside land, sea, air and space. It is not a management-system standard, and nothing in this cover or the doctrine it names maps onto ISO 27001, NIST guidance, or any organisational information-security control set. A reader arriving from a security questionnaire or a customer audit will not find that mapping here, because it does not exist.
What implementation means here
The agreement defines its own test. It "is implemented when it becomes part of national regulations, procedures, mechanisms as well as internal education, training, and exercises programs." Allies and NATO bodies "shall provide implementation details through the electronic reporting tool (e-Reporting)"; partner nations "are invited to provide their implementation details through the electronic reporting tool (e-Reporting)" - invited rather than obliged.
Ratification is a separate, earlier step: "Nations are invited to examine their ratification of the STANAG and, if they have not already done so, advise the NSO of their intention regarding its ratification and implementation," with responses recorded in the NATO Standardization Document Database.
Where it sits among the other agreements
STANAG 6514 does not stand alone. Its cover names a long list of sibling Allied joint doctrine publications as related: AJP-2 for intelligence, counter-intelligence and security; AJP-2.4 for signals intelligence; AJP-2.7 for joint intelligence, surveillance and reconnaissance; AJP-3 for the conduct of operations; AJP-3.5 for special operations; AJP-3.6 for electronic warfare; AJP-3.9 for joint targeting; AJP-3.10 for information operations; AJP-3.12 for military engineering; AJP-3.14 for force protection; AJP-3.19 for civil-military cooperation; AJP-3.21 for military police; AJP-5 for the planning of operations; and AJP-6 for communication and information systems. Every one of these is listed as informing context, not a binding requirement. The agreement is also reviewed under AAP-03.
What it does not do
It describes no certification, no notified body, no government quality assurance and no audit of an organisation. Its only stated check is its own periodic review under AAP-03, recorded in the NSDD. Edition 1 was promulgated on 29 January 2020, and the cover states plainly that it supersedes no earlier document.