**Higher duration = greater price sensitivity to interest rate changes.**

Duration ties together everything we've covered about volatility — it's a single number that captures the combined effect of both maturity and coupon:

- Longer maturity → higher duration → more volatile
- Lower coupon → higher duration → more volatile
- Zero coupon bond → duration equals its full term (most volatile of all — no coupons to cushion rate changes)

That's why duration is so useful — instead of comparing maturity AND coupon separately, you just compare one number.