TimelessMarket Theory
Breakouts & Trend Following · Module 4 of 8

The Turtle System

The rare complete professional system that's legitimately public — and the module where "breakout trading" finally becomes more than an entry signal.

In 1984, Chicago trader Richard Dennis bet his partner William Eckhardt that trading could be taught — recruited novices by newspaper ad, trained them for two weeks, and handed them firm capital. The trainees were nicknamed the Turtles. Two decades later, several original Turtles published the actual rules free of charge (with Dennis's permission), largely to spike the market in fake versions being sold by others. That document — The Original Turtle Trading Rules — is this module's primary source, and it teaches the single most important idea in the course: an entry signal is not a system.

The five decisions

The Turtle document is organized around the claim that a complete system decides everything: what to trade, how much, when to enter, when to exit a loser, when to exit a winner. Here is the whole machine, from the published rules:

Volatility unit. "N is simply the 20-day exponential moving average of the True Range, which is now more commonly known as the ATR." One N ≈ the market's average daily range.
Position size. One "Unit" is sized so 1 N of price movement ≈ 1% of account equity. Volatile markets automatically get fewer contracts; quiet markets more. Risk is equalized across markets — this, not the entry, is the system's real sophistication.
Entries. System 1: buy/sell a single tick beyond the 20-day high/low — but skip the signal if the previous breakout was a winner. System 2: same at the 55-day extreme, taken always. Both are pure Donchian. Units are added every ½ N in the trade's favor, up to a cap.
Stops. 2 N from entry — which, given the sizing rule, is exactly 2% of equity per Unit. "These stops were non-negotiable exits. If a particular commodity traded at the stop price, then the position was exited; each time, every time, without fail."
Exits. System 1: leave at the 10-day extreme against the position. System 2: at the 20-day. Note what this means — winners are never exited at a target. The system cannot take profits early, which is precisely how it guarantees catching the whole trend when one comes.

Why the exits were the hard part

A 10-day trailing exit routinely gives back a third or more of a large open profit before triggering. The rules are blunt that this is the emotionally hardest feature — most traders can't watch paper profits evaporate, so most traders shave the exit, and shaving the exit is what removes the rare giant winner that pays for everything. This is Livermore's "sitting" (Module 2) turned into an algorithm: the system sits tight for you, if you let it. The same theme runs through the trend traders interviewed in Market WizardsEd Seykota and Michael Marcus both describe versions of riding winners and cutting losers as the entire job (paraphrase; the interviews are worth reading whole).

What actually happened

Accounts of the experiment's results vary by source and by Turtle — figures like "80% a year over four years" circulate widely, and Michael Covel's history The Complete TurtleTrader documents both the successes and the wide dispersion between individual Turtles trading identical rules. That dispersion is itself the finding: with the same system, sizing discipline and psychological compliance still separated the best from the worst. The rules document ends on the same note — the authors' view is that consistency and discipline, not the specific parameters, were what Dennis actually proved teachable... for some.

One more honesty note: these exact parameters were traded on 1980s futures markets. The Turtles themselves warn that markets change; the published rules are a specimen of a complete system, not a kit to run unmodified today. Test before trusting — the sizing framework connects directly to the Risk & Survival course.

Reference pages: The Turtles (the story, with verified video) · Donchian channel breakout (the entry's playbook) · Risk & position sizing (the sizing math, generalized).

Assignment

Compute N for one market you follow (any charting tool's 20-period ATR on the daily). Then answer on paper: with a $10,000 account, how large is one Unit under the 1%-per-N rule, and where would the 2N stop sit? Most people who do this exercise are surprised in one of two directions — the position is far smaller than they normally trade, or the stop is far wider. Either surprise is the lesson.