Globally more is being spent on education than ever before. Understanding which educational inputs are most important for achievement is essential for improving efficiency of that spending. In this chapter, we review the literature that has used the education production function to model the relationship between educational inputs such as genetics, parental investments, school type, teacher quality and school resources, and educational outputs. We summarise the evidence from key studies that have produced credible estimates of the relationship between inputs and a variety of these different education and labour market outcomes. We conclude with some insights into potential avenues for future research.