ISB was founded in October 1951 as the American School of Brussels, initially to serve U.S. Department of Defense personnel and their families residing in the area.

[3] The ISB campus spans 162,134.6 m² (1,745,202 sq ft) of wooded land and features academic buildings, athletic facilities, and a performing arts center.

[4] Features include: ISB offers a wide range of academic programs with 45 International Baccalaureate courses available to students.

It is known for its commitment to inclusive education, providing opportunities for students with diverse needs, including the Intensive Learning Support (ILS) program.

To ensure continuity and an institutional memory in a population with a 25% turnover each year, the board strives for a balance of long-term and short-term members.