AMI remains headquartered in Amsterdam at 161-163 Koninginneweg in the building purchased by Maria Montessori and a neighbouring building purchased for expansion in 2010. AMI maintains a membership of over 5,000 individuals and it has now grown to encompass a global network of 42 legal affiliates in 36 countries including its USA Affiliated Office Association Montessori International of the United States which was established as a US 501(c)(3) not-for-profit organisation in 1972 by Mario Montessori, Richard Salzmann and Albert L. Ledgard, Jr.