[3] CAISL has partnerships with other institutions, such as the Gulbenkian Foundation, to support research initiatives into teaching methods, philanthropic outreach, and to host international conferences and cultural exhibitions.

CAISL's history begins in 1956, when the school is founded as St. Columban's School, by Irish professor Anthony A. McKenna, to serve the children of the American engineers who were in Portugal working on the Salazar Bridge (now 25 de Abril Bridge), in Lisbon, so that the children would be able to reintegrate back into the American system upon their departure from Portugal.

[9] Carlucci, who went on to serve as Deputy Director of the CIA and U.S. Secretary of Defense, played a prominent role in Portugal following the events of the 1974 Carnation Revolution, especially in maintaining good Luso-American relations.

[10] The initiative, led by a team of Gulbenkian researchers and CAISL professors, has been stated to have had profound effects in the teaching of science education in Portugal.

[13] CAISL has participated annually in the FIRST Lego League National Championship, and in the MAIS Middle School Robomed, international robotics competitions, since 2018.

[25] In 2013, CAISL hosted its 1st Conference on Early Childhood Learning, in cooperation with Pais&Filhos, an international child education publication.

[28][29] In 2018, CAISL has become an affiliate of the Sharing Foundation, an international philanthropic organization dedicated to promoting literacy and early childhood education.

[30] CAISL and Habitat for Humanity have partnered together since 2007 to send a delegation of students annually to help provide humanitarian relief to disadvantaged people.

[31] CAISL also has a long standing partnership with Banco Alimentar, the Portuguese food bank, providing volunteers for goods collection twice a year.

In 2022, CAISL also started collaborating with Associação Humanitária DOMUS/The Fuller Center for Housing, among other local and international charities.

[33][34] IMUN's keynote speakers have included politicians, diplomats, United Nations officials, and rights activists, such as internationally awarded author Richard Zimler and U.S.

The Carlucci American International School of Lisbon is governed by the Fundação Escola Americana de Lisboa (FEAL; Portuguese for "American School of Lisbon Foundation"), a private foundation under Portuguese Law, which is in turn governed by a three-member Board of Trustees.