This thesis studies dividend payout policy and its effect on firms' financial policy. It comprises three chapters. The first chapter, "The Real and Financial Effects of Dividend Rigidity", explores the consequences of an inflexible dividend policy. We study dividend smoothing in tandem with debt and investment. Avid smoothers resort to net debt to absorb cash flow variations because altering dividends is not fully available. Financially constrained firms are unable to rely entirely on debt to mitigate smoothing frictions, curbing investments to fund cash flow shocks. The effect persists for transitory cash flow, making it unlikely to be driven by heterogeneous growth options. We exploit differences in the loadings of smoothing on dividend s...