Using teachers’ skills from the Survey of Adult Skills (PIAAC) and students’ performance from the Programme for International Students Assessment (PISA) we exploit a multilevel model to investigate how much of the variation in student performance can be explained by teacher quality at the country level across a number of OECD countries. Results show how teachers’ skills seem to have positive effects on student achievement and explain part of the variation between countries in students’ achievement. National policies and efforts made from Education departments to improve teacher quality seem crucial to achieve both overall excellence and greater equity across countries.