The Inter-Agency Working Group (IAWG) on Reproductive Health in Crises was formed in 1995 and has grown to a broad-based network of over 1700 individual members representing 450 agencies. The IAWG is a highly collaborative coalition led by a Steering Committee of 18 United Nations agencies, international non-governmental organizations and academic institutions that works to expand and strengthen access to quality reproductive health services (RH) for persons displaced by conflict and natural disasters. Between 2002 and 2004, the IAWG undertook an evaluation of RH for refugees and internally displaced persons (IDP) in order to determine when and where RH services were provided and to identify gaps and challenges to better target resources and interventions. The findings revealed significant progress since 1995 in raising awareness and advancing RH services for conflict-affected populations, particularly those in stable refugee camps. However, major gaps in many RH components were present, including for gender-based violence, HIV/AIDS and sexually transmitted infections, safe motherhood and family planning, as well as youth-friendly services and services that encouraged male involvement. Furthermore, services for IDPs were found to be severely lacking and little was known about the SRH of populations in acute emergencies. A decade later, the humanitarian context has changed significantly, and the IAWG has undertaken an updated review to identify services, quantify progress, document gaps and determine future directions for programs, advocacy and funding priorities.