One of Wall Street's Riskiest Bets Returns

Investors are once again clamoring for a risky investment blamed for helping unleash the financial crisis: the synthetic CDO.

In a sign of how hard Wall Street is trying to satisfy voracious demand for higher returns amid rock-bottom interest rates, J.P. Morgan Chase & Co. and Morgan Stanley bankers in London are moving to assemble so-called synthetic collateralized debt obligations.

CDOs give investors a chance to bet on the creditworthiness of a basket of companies. Basic CDOs pool bonds and offer investors a slice of the pool. Synthetic CDOs pool, instead of the bonds themselves, insurance-like derivative contracts on the bonds.