Standard 60/40 portfolios have ~90% of risk in stocks (because stocks are 3-4× more volatile than bonds). Risk parity sizes each asset by 1/volatility so they contribute equally to portfolio risk. Then leverage scales the whole thing to your target vol. Bridgewater's All-Weather is the most famous example. Sharpe ratios are typically higher than 60/40, but the strategy requires leverage and is sensitive to correlation regime changes (e.g., 2022 when stocks AND bonds fell).