You have some money to invest. You can put it in a safe bank account that pays a steady, guaranteed interest rate. Or you can buy a diversified portfolio of stocks that will probably earn more over time but will bounce around in value. How much should you put in each? This chapter gives you a clear framework for that decision. It introduces the Capital Allocation Line (CAL) — a simple, powerful tool that shows every possible mix of risk and return you can create by blending a risk-free asset with a risky portfolio.