There are more students expecting a teaching career than there are teachers in the current population. On average across OECD countries, 4.2% of 15-year-old students expect to work as teachers--a greater proportion than the share of teachers in the adult population. An analysis of 2015 data from the Programme for International Student Assessment (PISA) examines differences between countries regarding the extent to which 15-year-old students, high-achieving students and students with non-traditional profiles expect to work as teachers. It also attempts to explain these differences between countries by relating them to the social status, monetary compensation and working conditions enjoyed by teachers in different countries. The skills gap between students who expect a career in teaching and those who expect a career as another type of professional is often larger in low-performing versus top-performing countries. Countries with higher teacher salaries (relative to GDP) and higher perceptions of the social value of the teaching profession have, on average, larger shares of students who expect to work as teachers. A growing awareness that the quality of schooling critically depends on teachers' skills has led to mounting concerns among policy makers about the difficulty of attracting high achieving and motivated candidates into the teaching profession. Concerns are even more significant in countries that suffer from shortages of teachers or where teacher shortages are worsening over time. Education systems could do more to encourage and support the pursuit of a teaching career among all motivated students. To promote teaching as a career, in particular for top-performing students, job quality matters at least as much as pay. Transforming the work organisation of schools, involving teachers in school decision making, enhancing their leadership responsibilities and promoting teaching as a demanding, but fulfilling, profession are promising policy levers.