The Crisis Response Operation Core (CROC) is a flagship European Union defence project under development as part of Permanent Structured Cooperation (PESCO).

[1] CROC is intended to be a 60,000 head military force composed of three divisions of four battalions each.

While it does not establish any form of "European army", it foresees a deployable, interoperable force under a single command.

[2] Germany is leading the project, but France is also heavily involved as the subject is tied to President Emmanuel Macron's proposal to create a standing intervention force.

[3] As of September 2021, Cyprus, France, Germany, Greece, Italy, and Spain are participating in CROC, and other member states could join.