Essay 1 examines the impact of geographic concentration of institutional investors on corporate governance and firm value. We find that firms whose large institutions are closely located to each other experience higher forced CEO turnover-performance sensitivity, more frequent proxy voting against management, higher returns around CEO turnover announcements and Schedule 13D filings, larger increases in Tobin’s q (ROA), and greater liquidity. These results are robust to using the introduction of new airline routes as an exogenous source of variation in proximity and to using an instrumental variable approach. Our results suggest that geographic concentration of investors increases monitoring effectiveness. Essay 2 analyses the importance of ...