Say you want to invest in fixed-income instruments. You know that interest rates are bound to rise, but not how soon and by how much. If you invest today at low interest rates for the long run and then rates rise after a year, you wouldn't benefit from it. To ensure that you invest in assets that give the highest interest rate possible, you ladder-up. Fixed-income laddering refers to investing in instruments with different maturities; some in a 6-month instruments, some in 1-year instruments, some in 18-month instruments and so on. This ensures that bonds mature over time and you can immediately reinvest the returns at prevailing interest rates.