Book excerpt: This paper shows that the impact of labor income risk on the cross-section of expected stock returns depends crucially on the horizon. Using a flexible empirical approach that allows us to include multiple horizons simultaneously, we find robust evidence that the two- to four-year horizon strongly dominates. Labor income risk at this medium term horizon carries a highly significant price of risk, while at other horizons it does not. A simple two-factor model that includes the equity market return and labor income risk at the medium term horizon can explain a striking 71% of the cross-sectional variation of 25 size book-to-market and 25 size-investment portfolios. This is a significant improvement over the standard human capital CAPM with quarterly labor income growth that has an R-squared of only 7%. Also, labor income risk generates significant adjustments to the composition of the optimal risky equity portfolio at the medium term horizon. These results are consistent with wage stickiness, where wages are reset every two to four years.