In a firm with multiple hierarchical levels, efficient promotion decisions can require information concerning worker ability levels to be shared within the firm. We explore practices that improve intra-firm employer learning and reduce talent hoarding given heterogeneous worker visibility. We find that firms can employ managerial bonuses and job rotation to improve intra-firm employer learning and avoid talent hoarding, but the presence of visible workers can increase the likelihood of talent hoarding. Also, when equilibrium is characterized by talent hoarding, less visible workers are disadvantaged in hiring and promotion. We compare our theoretical results to findings in the empirical literature.