The Long-Term Capital Management crisis was a 1998 financial emergency in which an acclaimed hedge fund’s leveraged bets became dangerously difficult to unwind after Russia defaulted on its debt. LTCM had built its reputation on sophisticated models and strategies designed to profit from temporary price divergences. Yet its dependence on borrowed money, illiquid markets, and increasingly imitative competitors made it vulnerable to a moment when almost nobody was willing to take the other side of a trade. The fund’s rescue by thirteen Wall Street banks preserved it through the immediate turmoil; the deeper lesson was that expertise without diversity can leave a market unable to correct itself.