This volume is a review of plant health research and its implementation by the International Institute of Tropical Agriculture (IITA) and its collaborators worldwide to celebrate IITA’s fiftieth anniversary. It addresses plant health issues of global importance in sub-Saharan Africa, including hunger, poverty and threats to economic development and the environment. The volume addresses new and emerging plant health challenges in particular, including the effects of climate change, the significant increase in international trade which introduces invasive species, the rapid loss of biological diversity and new pest pathways. The volume’s overall goal is to encourage sustainable and productive agriculture in Africa, feeding into local value chains and improving the livelihood of Africans across the continent. This introduction to the individual chapters that describe specific plant health issues provides a historical context for plant health research and implementation and gives an overview of the structure of the text as a whole.