ICMICA/MIIC Pax Romana was created in 1947 and now has members in more than 54 countries from every continent, as well as several contact groups and individual members. The international headquarters is in Geneva, Switzerland. Pax Romana, initially founded in 1921, is made up of two complementary organizations or branches:
The Plenary Assembly of ICMICA/MIIC Pax Romana meets every four years to decide statutory matters and action plans 
for the period and to appoint the 17 members of the International Council, including a President, Vice-Presidents and Secretary General. The last Plenary Assembly took place in Nairobi, Kenya in July 2008.
ICMICA/MIIC Pax Romana has five Vice-Presidents; one for each region of the world. Each region has a small group of volunteers who provide the regional cooperation. At present, these groups are in Nairobi for Africa, Seoul for Asia/Pacific, Mesvres in France for Europe, Santiago in Republic Dominica for Latin America and the Caribbean and Miami for North America.
- ICMICA/MIIC : whose members are the federations of intellectuals and professionals.
- IMCS/MIEC : The International Movement of Catholic Students, whose members are the federations of young students. The headquarters is in Paris, France.
In 2008 Pax Romana ICMICA/MIIC elected the following International Team:
- Prof. Dr. Javier María IGUIÑIZ ECHEVERRIA, Professor of Economics, Pontifical Catholic University of Peru.
- Ms. Laurence KWARK, who previously worked for CCFD in Paris, France.
- Fr. Luis Maria GOICOECHEA, Rector of Seminary in Vitoria, Basque Country.