We study a novel aspect of a firm’s capital structure, namely, the profile of its debt maturity dates. In a simple theoretical framework we show that the dispersion of debt maturities constitutes an important dimension of capital structure choice, driven by firm characteristics and debt rollover risk. Guided by these predictions we establish two main empirical results. First, using an exogenous shock to rollover risk, we document a significant increase in maturity dispersion for firms that need to roll over maturing debt. Second, we find strong support that maturities of newly issued debt are influenced by pre-existing maturity profiles.