David Johnson is a chartered educational psychologist. He is a reader in comparative and international education and Professorial Fellow, St Antony’s College, University of Oxford. He teaches a number of papers in comparative education including on the history and politics of education in Africa and on the politics of educational policy. He works closely with African education officials on the use of data for educational policymaking including recently in Sudan, Sierra Leone, and Rwanda, and significantly in Nigeria where he carried out assessments of teachers’ knowledge and professional competencies across 11 states. Currently, he is assessing students in a randomised controlled trial on teacher incentives in Rwanda and a carrying out a study on progression in learning in Sierra Leone. He is an advisor to PricewaterhouseCoopers on learning assessments on the DFID–funded Girls Education Challenge.