“Take a typical three-hundred-million-dollar CMO. It would be divided into three tranches, or slices of a hundred million dollars each. Investors in each tranche received interest payments. But the owners of the first tranche received all principal repayments from all three hundred million dollars of mortgage bonds held in trust. Not until first tranche holders were entirely paid off did second tranche investors receive any prepayments. Not until both first and second tranche investors had been entirely paid off did the holder of a third tranche certificate receive prepayments.” InvestmentWall StreetCdoTranches Book:Liar's Poker Source: Liar's Poker