The Turtle Trading System Explained: Richard Dennis's Experiment That Proved Anyone Can Learn to Trade

In 1983, a futures trader made a bet that trading could be taught to complete strangers from a written rulebook. The system that came out of it is still the clearest real-world proof that discipline can outperform talent.

Most trading strategies get judged on backtests. The Turtle Trading system got judged on something rarer: a live, funded, multi-year experiment with real money and ordinary people who had never traded before.

Commodities trader Richard Dennis had turned a few thousand dollars into several hundred million dollars trading futures, and he believed his edge came from a learnable, rules-based method rather than any natural gift. His trading partner, mathematician William Eckhardt, disagreed - he thought Dennis's success came from a trait that couldn't be taught. In 1983, they settled it the only way two traders could: with a bet, and real capital on the line.

This guide walks through what the Turtles were actually taught, the exact entry and exit rules behind the system, how they sized positions using volatility instead of guesswork, what happened when the rules produced painful losing stretches, and how the same core logic still applies to breakout trading in individual stocks today.

The Experiment: Teaching Trading to Complete Beginners

Dennis and Eckhardt ran a newspaper ad, interviewed a large pool of applicants, and selected 23 people with little or no trading background - among them a professional blackjack player, a fantasy game designer, and an accountant. Each recruit trained for roughly two weeks in a fully mechanical trading system, then received a funded account to trade Dennis's rules with his own capital.

The group, nicknamed the "Turtles," went on to generate more than $100 million in combined profits over the following four years - a result documented in detail in Michael Covel's The Complete TurtleTrader and in Way of the Turtle, written by one of the original Turtles, Curtis Faith. The exact total varies slightly across sources, but the outcome that mattered was never in dispute: ordinary people, given a written rulebook and the discipline to follow it, produced a professional-grade track record.

The Core Rules: Two Breakout Systems Running in Parallel

The Turtles traded two systems side by side across a diversified basket of futures markets - currencies, bonds, metals, energy, and agricultural commodities - specifically to keep positions spread across markets that didn't all move together.

The System 1 "skip rule" is the least intuitive part of the system and the part most beginners get wrong when they try to reconstruct it from memory: the Turtles believed that after a winning breakout, the market had already "used up" some of its trending energy, so they deliberately sat out the very next signal in that direction and waited for System 2's wider net or a fresh System 1 setup instead.

The gap between entry and exit windows is the system's real engine. A 20-day entry paired with a 10-day exit means a position gets cut on far less adverse evidence than it took to justify getting in - the system is built to lose small and often, and let the rare large winners run uninterrupted.

Position Sizing: The "N" That Made Every Trade Comparable

The most sophisticated part of the Turtle system had nothing to do with entries or exits - it was how positions were sized.

The Turtles used "N," a 20-day average of the true range, which is the exact calculation now widely known as the Average True Range (ATR). Rather than trading a fixed number of contracts, each position was sized so that a move of one N in price corresponded to roughly 1% of total account equity. A volatile market like crude oil got a smaller position; a calmer market got a larger one - for the same dollar risk on either trade.

Hard limits kept any single market or theme from dominating the book:

This is the piece of the system that has aged the best. Position sizing by volatility rather than by a flat share count or dollar amount is now standard practice across professional trend-following, and it solves a problem every retail trader eventually runs into: a fixed position size treats a calm utility stock and a wild small-cap the same, when the actual dollar risk they carry is nothing alike.

Why the Rules Worked - and Why They Were So Hard to Follow

Trend-following systems like this one share an uncomfortable statistical signature: they lose more often than they win. Most breakouts fail and get stopped out for a small loss. The system's entire profitability rests on a small number of trades running far enough to more than pay for every losing trade that came before it.

That structure is mathematically sound and psychologically brutal. Drawdowns of 50% or more in account equity were a normal, documented part of following the rules - and several of the original Turtles reportedly abandoned or second-guessed the system during exactly those stretches, only to watch it recover afterward. The rulebook didn't fail; the discipline to keep following it during a losing streak did, for some.

Applying Turtle-Style Rules to Individual Stocks Today

The literal futures ruleset is less of an edge today than it was in 1983 - decades of trend-following funds now watch the same breakout levels, which crowds the exact signal the Turtles exploited. But the underlying framework translates cleanly to individual equities and ETFs:

• Use a 20-day high as a shorter-term breakout signal, the same window System 1 traded, for stocks showing early momentum.
• Use a 55-day high (or a wider 52-week high) as a longer-term trend-confirmation signal, the way System 2 was built to catch the biggest, most durable moves rather than every minor breakout.
• Size the position by the stock's own ATR, not a flat share count. A stock with a wide daily range needs a smaller position than a quiet one to carry the same dollar risk - exactly the logic behind "N."
• Set the exit before the entry, not after. The Turtles' fast exit windows (10 and 20 days) existed specifically so a losing trade never had the chance to become a large one.

The single hardest part of the original experiment to replicate isn't the arithmetic - it's taking every signal the system generates and exiting exactly when the rule says to, even when it feels wrong. That's precisely why Dennis and Eckhardt recruited people with no prior trading habits: a beginner following the rulebook had nothing to unlearn.

Automating the Discipline the Turtles Had to Learn by Hand

In 1983, following a 20-day breakout rule meant checking price charts by hand, every day, across dozens of markets. That manual monitoring was arguably a bigger obstacle to consistent execution than the rules themselves.

Frequently Asked Questions

What was the Turtle Trading experiment?

In 1983, commodities trader Richard Dennis bet his trading partner William Eckhardt that trading could be taught to complete beginners using a written set of rules. They selected 23 people with little or no trading background, trained them for about two weeks, and funded their accounts. The group, nicknamed the Turtles, generated more than $100 million in combined profits over the following four years.

What are the actual Turtle Trading entry and exit rules?

System 1 entered on a breakout to a 20-day high or low, but skipped the signal if the prior System 1 trade had been a winner. System 2 entered on a breakout to a 55-day high or low with no skip rule. System 1 exited on a reversal to a 10-day low or high; System 2 exited on a reversal to a 20-day low or high.

How did the Turtles decide how big a position to take?

Position size was based on volatility using "N," a 20-day average true range. Each unit was sized so one N of price movement equaled roughly 1% of account equity. Caps limited concentration: 4 units per market, 6 units across correlated markets, and 12 units total in a single direction.

Did the Turtle Trading system actually work, and does it still work today?

It worked well enough to turn into more than $100 million over about four years, but it also produced documented drawdowns of 50% or more that caused some Turtles to abandon it mid-stretch. The literal futures ruleset is more crowded today, but the core framework - mechanical entries, faster mechanical exits, and volatility-based sizing - is still a standard foundation for rules-based trend following.

How can an individual stock investor apply Turtle-style rules today?

Treat a 20-day high as a shorter-term breakout signal and a 55-day or 52-week high as a longer-term trend-confirmation signal, then size positions and set trailing stops using the stock's own Average True Range instead of a flat share count or percentage.

Related Reading

• Breakout Trading: How to Identify and Trade Price Breakouts - the broader strategy family the Turtle entries belong to
• 52-Week High Alert: The Breakout Strategy Most Traders Get Wrong - a longer-window breakout signal in the same spirit as System 2
• Average True Range (ATR) Explained - the modern name for the Turtles' volatility measure, "N"
• Trading Risk Management Guide - position sizing and drawdown control for any rules-based system
• Trading Psychology: How to Master Your Emotions and Trade with Discipline - the discipline problem that broke several of the original Turtles