Every two years the WHO publishes a model list which countries use to develop national lists of essential medicines. Most low- and middle-income countries have adopted and adapted the WHO model list concept and developed their own essential medicine lists in line with their disease and treatment priorities. But the lists are only part of the system. Medicines on the list also have to be registered for use in a country and the pharmaceutical industry has to apply to register its products. After approval by regulatory authorities, they are listed on national drug registers. But there appear to be mismatches between lists of essential medicines and lists of registered medicine products in some countries. One study in Uganda showed that almost half (49%) of essential medicines weren’t registered for use in the country. Looking to fill a gap in information about these mismatches, researchers conducted a study in Kenya, Uganda and Tanzania. They compared the antimicrobial products on national drug registers with those on the three countries’ essential medicine lists.