5, 15, 50, 150: when to redraw the org chart

Series「People Don't Follow the Org Chart」 · Part 2 of 13 · Part 1 · How people group
Prologue：The people who aren't on the org chart

A Japan entity grows from three people to thirty, and the head still runs it the way he did at three: every decision his, everyone comes straight to him. At thirty it starts to jam. At fifty it stops. Most people call this "the boss won't delegate." A more precise description: the org chart needed redrawing, and nobody knew when.

Not a number, a sequence

In the 1990s the anthropologist Robin Dunbar proposed that there is a ceiling on the number of stable social relationships a person can maintain, around 150. The number has been quoted so often that it is usually treated as the whole finding. The more useful part of his work is the sequence: about 5 intimates, 15 people you can rely on, 50 you stay in regular contact with, 150 whose names and relationships you know. Each layer is roughly three times the one before.

The dispute should be stated plainly. Dunbar's number comes from a correlation between neocortex size and group size in primates, extrapolated to humans. A 2021 reanalysis of the same data produced confidence intervals from a handful to several hundred and concluded that 150 has no statistical privilege. Supporters point out that these layers keep showing up in military units, village sizes and social network data.

My use is this: not 150 as a biological constant, but the sequence as empirical thresholds. They mark the points at which the way relationships are maintained has to change. The exact numbers can drift.

At each step, the mechanism changes

Up to 5, no organization is needed. Everyone knows everything; division of labor is tacit.

Around 15 is the ceiling of one team. One person can still judge everyone's work and state directly, but who owns what has to be explicit. This is the first redraw: from "all of us" to "a few roles."

Around 50, one person can no longer see everyone, and a middle layer appears. This is the second redraw and the easiest to get wrong. Middle management isn't the boss's job cut into pieces; it's an added layer of information filtering. The "good news only" pattern in my organizational diagnosis almost always appears here.

Around 150, people stop knowing each other. An organization held together by relationships ends here; after this it is held together by systems, grades and written rules. The third redraw: from people managing people to systems managing people.

The design decision: redraw one step early

Charts usually get redrawn after the jam, six months late. Treat these numbers as tripwires and act before you reach them.

Approaching 15: define three or four roles, one owner each, and have the head manage only those people directly. Approaching 50: before appointing middle managers, decide what they may filter and what they may not, and write down the three kinds of news that must always travel up. Approaching 150: start writing grade and pay rules. Setting pay by relationship works until then; after it, it always blows up.

Japan adds one variable. Japanese employees' sense of place is strong (see the previous post), so a team under 15 coheres more tightly than its Western equivalent, but the 50 threshold is harder to cross, because adding a middle layer means cutting one place into several. Cut by business, not by function, so each place has complete work to do.

Back to the diagnosis

The patterns layer of my organizational diagnosis includes "does the management style match the size," and this sequence is the ruler. A 60-person company run like a 15-person one is a bigger problem than any individual manager. When two heads work, a separate post, also depends on size.

How many people does your company have now, and at how many was the chart drawn?

In this series
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Next：The favor ledger is more honest than the org chart