We have lost control of our data

I believe that we are creating more data than we can manage.

The primary output of most workers is information. Day after day we produce more. That is our job.

Yet we have utterly neglected the task of organising, sorting, and managing it.

I have not seen a corporate system in the last decade that was not totally broken because of the volume of unmanaged information.

Search doesn’t help

At one point we thought that search would get us out of this mess. But search does not solve the corporate information problem.

File systems are disparate; the level of duplication is already too great; and the cues that Google uses to determine what’s useful — the links that are the fabric of the internet — just don’t exist at work.

You can search for things, but the results are garbage.

Find your stuff again

And so the purpose of Johnny.Decimal is simple.

It enables you to:

  • find things
  • quicker, with
  • less stress, and
  • more confidence than you can today.

You will be able to find the latest and only version of a thing.

You will be confident that your file system is not strewn with duplicate versions that are being independently updated.

You will finally be in control of your project’s data.

It’s time to get organised

There are a couple of core concepts, and they’re so simple you’ll wonder why you haven’t thought of them before.

It’s worth mentioning at this point that all of this is free, and it’s possible to implement it without any additional tools.

  1. Take everything you need to organise and sort it in to, at most, ten large buckets.
  2. Make sure the buckets are unambiguously different.
  3. Put a label on each bucket.

This forces you to group things quite broadly, but that’s the point.

We call these buckets your areas.

An area might be Project management or Documentation.

Go through each of your new areas and repeat the process.

This creates your categories.

A category within the Project management area might be Schedule.

A category within Documentation might be System design.

Now we have ten areas which contain ten categories each. That’s a hundred categories at the very most. It’s very unlikely you will end up with a hundred categories.

What’s a category? It’s just a collection of stuff. Project schedules. Test plans. Design documents. Security reviews. Contracts.

Any type of work you do can become a category.

The point is that you’ve defined these categories, each of which is contained within a broader area. You do this when you set up your system, which we’ll get to shortly.

We give each category a number

Remember they’re grouped in tens, so our first ten categories will be numbers 10-19 and they will all be related to each other.

Let’s say 10-19 is our Project management area.

Category 11 might be Scope, 12 Schedule, and so on.

A Johnny.Decimal number looks like this:

42.12 12.03 53.17

They’re short, memorable, and can be spoken out loud.

They’re always two digits, a decimal point, and two more digits.

Say it like “forty-two twelve” or “twelve dot oh-three”.

Before the decimal: category

The decimal point is there to break the number up, but more importantly to remind you that the number before the decimal is the important part. It’s the category.

The category’s number tells you which area it’s in. If your category starts with the digit 1, that’s something to do with Project management.

At a glance, you know what the number contains. You’ll be astonished at how many of your category numbers you remember.

After the decimal: ID

The number after the decimal is just a counter. We call it the ID: it starts at .01 and increases with each thing you create.

In these examples, 42.12 is the 12th thing you’ve saved in your 42 category.

The 3rd thing you’ve saved in your 12 Schedule category might be 12.03 Schedule baseline March 2023.

The ID doesn’t have any relevance to the item itself – remember, it’s just a counter.

Many, many reasons.

Organise your files

The most obvious use of Johnny.Decimal is in organising your folder structure.

Screenshot of a macOS Finder window showing a hierarchical folder structure.

This is a folder structure for a generic IT project. (The reasoning behind the folder naming structure will be explained later.)

Notice how we have five areas, each with a couple of categories. None of the areas or categories overlap. There’s only one place anything can ever be.

Even if you weren’t familiar with this folder structure, you’d be able to find your way to the system design directory.


Stop reinventing the wheel. I use the same 10-19 Project management structure for every project. I have it committed to memory. (This is how I can find my scope statement in ten seconds.)

This one is modelled on PMP®. Either copy it, or adapt for whatever framework you use.

Nothing is more than two clicks away

An important restriction of the system is that you’re not allowed to create any folders inside a Johnny.Decimal folder.

This means that you’ll never get lost in layers upon layers of folders. It also makes you create quite specific folders for each thing, ensuring that you can always find what you want.

Tell people where things are

“Hey Kristy, where can I find the test case for this component?”

“Forty-one dot twelve.”

Thanks, Kristy.

Fix your email

Put the Johnny.Decimal number in your email subject and you’ve instantly categorised everything. Your colleagues will think you have mystical powers because you’ll actually be able to find email again.

Display it on printed copies

Rather than including the complete file path on printed documentation, just add the Johnny.Decimal number.

Open files and folders instantly

Because your folders contain the Johnny.Decimal number, you can open them without reaching for the mouse.

Mac users

Press Cmd + Space to bring up Spotlight. Type a Johnny.Decimal number. Press Return.

(If you like this sort of thing, check out Alfred.)

Windows users

Hit the Windows key. Type a Johnny.Decimal number in the Search box. Press Return.

Command-line users

Tab completion becomes a joy when your folders start with structured, predictable numbers. Or use a small shell script to pop you in to any folder instantly:

~ $ cjd 11.01

11.01 Scope statement $

Tag things in real life

Managing physical objects? Write the Johnny.Decimal number on a sticky note.

By now you either see the power of this and want more, or you’re confused and sad.

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