Biofortification, the development of nutrient-dense staple crops, has been promoted both as a solution to ‘hidden hunger’ among poor populations in the developing world (Nestel et al 2006) and as an exemplar of the kind of global public goods research for which the CGIAR system is renowned (Dalrymple 2008). As an interdisciplinary field of research and development linking crop science with human nutrition and public health (CIAT and IFPRI 2002), biofortification presents both challenges and opportunities for an international agricultural research system oriented towards genetics-led crop improvement (Anderson et al 1991). This chapter traces developments in biofortification research over a fifteen-year period during which it emerged from the margins of the CGIAR to become a priority for research investment (von Braun et al 2008).