Regulatory reforms since the financial crisis have sought to make the financial system safer and severe financial crises less likely. But by limiting the ability of regulated institutions to increase their balance sheet size, reforms—such as the Dodd-Frank Act in the United States and the Basel Committee’s Basel III bank regulations internationally—might reduce the total intermediation capacity of the financial system during normal times. Decreases in intermediation capacity may then lead to decreased liquidity in markets in which the regulated institutions intermediate significant trading activity. While recent commentary by market participants claims that this is indeed the case—a Wall Street Journal article [subscription required] notes that “[t]hree-quarters of institutional bond investors say that liquidity provided by bond dealers has declined in the past year…”—empirical studies have struggled to find evidence supporting this narrative. In this post, we summarize the findings of our recent article in the Journal of Monetary Economics that addresses the apparent disconnect between the market-participant commentary and the empirical evidence by focusing on the relationship between bond-level liquidity and financial institutions’ balance sheet constraints.