This chapter provides an overview of health data among migrants on the Central Mediterranean Route, using a case-based approach. It outlines how data are currently collected and what are the strengths and weaknesses of these health information systems. Examples from Libya, Italy, Germany, the United Kingdom and a transnational electronic health record system show the variety of systems in place. Current health information systems that capture migrant health are very heterogenous, often not harmonized and sometimes time-limited. As a result, information on migrant health is limited. Better recording of migration-relevant information in routine systems, access of migrants to routine care and collection of their data, as well as harmonization of variables and systems, are needed to inform public health policy and health-care delivery.