The world faces a critical shortage of teachers, hindering the achievement of SDG 4 and the Education 2030 agenda. This first Global Report on Teachers stresses the urgency of this challenge and calls for immediate action. Exposing a projected deficit of 44 million primary and secondary education teachers by 2030, the report examines the complexity of the crisis, from sub-Saharan Africa’s need for 15 million more teachers to a decline in the attractiveness of the profession and subsequent retention challenges in higher-income countries. Filling a void in the field and grounded in new data, the report calls for international cooperation and increased education investment, offering a roadmap to empower teachers and to find policy solutions to ensure every learner is taught by a qualified, motivated and well-supported teachers.