The ABCA Program's purpose is to optimize interoperability between member armies on combined operations. Current membership consists of the
United States, the
United Kingdom,
Canada,
Australia and
New Zealand.In 1947, the Armies of the United States, Britain and Canada joined into a standardisation agreement as a means of continuing to capitalize on the close cooperation during
World War II and to improve standardization. The group became known as the ABC Armies. In 1963, Australia joined the organization, and on 10 Oct 64 the four member armies signed a new standardization agreement to formally create the current ABCA program. In 1965 New Zealand was granted observer status under Australia's sponsorship. New Zealand became a full member of ABCA in late 2006.
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