What Is Regime?
Market regime describes the dominant condition or "state" of the market at any given time. The four primary regimes are: trending volatile (strong directional moves with high volatility), trending quiet (steady directional movement with low volatility), ranging volatile (choppy, directionless with large swings), and ranging quiet (tight consolidation with low volatility).
How Regime Works
Different strategies work in different regimes: trend-following strategies excel in trending markets, mean-reversion strategies work in ranging markets, and volatility strategies profit in volatile regimes. A strategy that worked brilliantly last month might fail completely this month because the regime changed — not because the strategy is broken.
Why It Matters for Traders
Regime detection is arguably the most valuable meta-skill in trading. If you can identify the current regime, you know which strategies to deploy and which to bench. Indicators like ADX (trend strength), Bollinger Band width (volatility), and ATR relative to its average help classify regimes. The most costly mistake is using a trending strategy in a ranging market or vice versa.