This thesis consists of three essays in which I seek to understand how internal firm practices affect long-term outcomes for workers. In each essay, I exploit variation in external labor market conditions to help identify changes inside the firm. In the first chapter, I explore whether employer learning about worker quality is asymmetric. Do incumbent employers learn faster about their workers than does the outside market? I develop a methodology to measure the extent to which employers learn by relating the pay change distribution to various features of ability distributions. I exploit three distinct external labor market factors to generate differences in ability distributions, including the reason why workers left the previous job, economic conditions when entering a job, and occupational differences. I find that asymmetric learning is prevalent in the labor market with effects on wage-change distributions that are significant, both statistically and in terms of economic magnitudes.