This paper presents a framework for understanding the effects of automation and other technological changes on labor demand. It uses this framework to interpret changes in US employment over the recent past. The key idea is that automation shifts the task content of production against labor, reducing the labor share in value added. However, new tasks, which labor has a comparative advantage in, shift the task content of production in favor of labor, increasing the labor share and labor demand. The authors show how changes in the task content of production can be inferred from industry-level data. Their empirical decomposition suggests that the slower growth of employment over the last three decades is due to an acceleration in the displacement effect, especially in manufacturing, a weaker reinstatement effect, and slower growth of productivity than in previous decades. The paper argues that automation and new tasks have different impacts on labor demand. Automation displaces labor from tasks it was previously engaged in, reducing the labor share in value added. New tasks, on the other hand, reinstate labor into a broader range of tasks, increasing the labor share and labor demand. The authors use a task-based framework to analyze how these effects interact. They show that the labor share in value added is determined by the relative prices of tasks and the elasticity of substitution between tasks. The task content of production, which is the allocation of tasks to capital and labor, is a key determinant of labor demand. The authors use industry data to decompose changes in the wage bill into productivity, composition, and substitution effects, as well as changes in the task content of production. They find that the slowdown in labor demand growth over the last three decades is due to a combination of anemic productivity growth and adverse shifts in the task content of production. They also find that the introduction of new tasks has been slower in recent years, which has not been offset by the creation of new tasks. The paper concludes that the future of work depends on the mixture of new technologies and how these change the task content of production.This paper presents a framework for understanding the effects of automation and other technological changes on labor demand. It uses this framework to interpret changes in US employment over the recent past. The key idea is that automation shifts the task content of production against labor, reducing the labor share in value added. However, new tasks, which labor has a comparative advantage in, shift the task content of production in favor of labor, increasing the labor share and labor demand. The authors show how changes in the task content of production can be inferred from industry-level data. Their empirical decomposition suggests that the slower growth of employment over the last three decades is due to an acceleration in the displacement effect, especially in manufacturing, a weaker reinstatement effect, and slower growth of productivity than in previous decades. The paper argues that automation and new tasks have different impacts on labor demand. Automation displaces labor from tasks it was previously engaged in, reducing the labor share in value added. New tasks, on the other hand, reinstate labor into a broader range of tasks, increasing the labor share and labor demand. The authors use a task-based framework to analyze how these effects interact. They show that the labor share in value added is determined by the relative prices of tasks and the elasticity of substitution between tasks. The task content of production, which is the allocation of tasks to capital and labor, is a key determinant of labor demand. The authors use industry data to decompose changes in the wage bill into productivity, composition, and substitution effects, as well as changes in the task content of production. They find that the slowdown in labor demand growth over the last three decades is due to a combination of anemic productivity growth and adverse shifts in the task content of production. They also find that the introduction of new tasks has been slower in recent years, which has not been offset by the creation of new tasks. The paper concludes that the future of work depends on the mixture of new technologies and how these change the task content of production.