A well-functioning supply chain is critical to the delivery of vaccines and other medical supplies. Where supply chains are broken or where inadequate information distorts a clear picture of health needs and medical supply availability, the result can be stock-outs of essential medicines and death due to preventable causes. Open Logistics Management Information System (OpenLMIS) is an effort to improve health systems through the creation of a shared platform of health supply chain tools and knowledge. It seeks to address the whole of the supply chain, rather than isolated efforts that address only a particular disease or supply chain layer. Built using open source software, OpenLMIS supports shared investment in and benefit from a system that is interoperable with other medical information systems, while being customizable to the unique needs of specific countries and projects. It is currently being used in Mozambique, Tanzania, Zambia, and Benin.