The panel and poster session entitled “Strengthening Mathematics in the Developing World” at the 2018 International Congress of Mathematicians (ICM) in Rio de Janeiro, Brazil was organized by the Commission for Developing Countries (CDC) of the International Mathematical Union (IMU). The objective was to share information about mathematical development activities with mathematicians at the ICM and to serve as a catalyst for interactions between mathematicians, organizations and funding agencies. The panel had representatives from seven organizations including international mathematical unions, commissions supporting the developing world, supporting women, a funding agency and the mathematical society of the host nation to the ICM (Brazil). There were ten other organizations supporting the developing world represented in the poster session, several of which work closely with the organizations in the panel. The panel and poster session had an attendance of approximately 400 and led to a large number of interactions between the representatives of the organizations and the audience.