Child Soldiers International had a London headquarters and conducted research, advocacy and capacity building in countries across the world.

Programmes included: Central African Republic;[6] Democratic Republic of Congo;[7] Afghanistan;[8] India;[9] Myanmar;[10] Thailand;[11] Child Soldiers International delivered research findings and policy recommendations to the United Nations Security Council in New York and the UN Committee on the Rights of the Child in Geneva, Switzerland.

According to UN documents, in relation to the adoption and enforcement of the Optional Protocol on the Involvement of Children in Armed Conflict, Child Soldiers International played "a key role in ensuring implementation at every level."

The guide summarizes the process of the treaty's adoption, its fundamental provisions, and recommends that certain activities be undertaken to ensure its full enforcement.

Annual audited financial statements[14] were filed with the UK Charity Commission,[15] Companies House,[16] and published on Child Soldiers International's own website.