On Monday, October 19, 1987, the Dow Jones Industrial Average plunged 22.6 percent, nearly twice the next largest drop—the 12.8 percent Great Crash on October 28, 1929, that heralded the Great Depression.

What stands out is not the scale of the decline—it is far smaller than the 90 percent peak-to-trough drop of the early 1930s—but its extraordinary speed. A range of financial market and institutional dislocations accompanied this rapid plunge, threatening not just stocks and related instruments (domestically and globally), but also the U.S. supply of credit and the payments system. As a result, Black Monday has been labeled “the first contemporary global financial crisis.” And, a new book—A First-Class Catastrophe—narrates the tense human drama that it created for market and government officials. A movie seems sure to follow.

Our reading of history suggests that it was only with a great dose of serendipity that we escaped catastrophe in 1987. Knowing that fortune usually favors the well prepared, the near-collapse on Black Monday prompted market participants, regulators, the lender of last resort, and legislators to fortify the financial system.

In this post, we review key aspects of the 1987 crash and discuss subsequent steps taken to improve the resilience of the financial system. We also highlight a key lingering vulnerability: we still have no mechanism for managing the insolvency of critical payment, clearing and settlement (PCS) institutions....