There is at least one person in your business who, if they gave notice tomorrow, would cause a genuinely bad month. In a lot of small businesses there are two or three.
That is normal. What is not normal is going years without doing anything about it.
Identify them honestly
Not the most senior. Not the best. The one whose absence would break something.
Ask:
- Who is the only person who can do a specific thing?
- Who holds relationships that would leave with them?
- Who knows why things are the way they are?
- Whose passwords, accounts and access nobody else has?
- Who does people ask when they are stuck?
- Whose work is invisible until it stops?
That last one catches people out. The person quietly holding the operation together is frequently not the person you would name first.
What actually walks out the door
Process knowledge. How things are done, and the hundred small decisions that are not written anywhere.
Relationships. Customers who call them, suppliers who do favours for them, the subcontractor who fits you in because of a long relationship.
Judgement. Which jobs are worth taking. Which customers are trouble. What a fair price is for an unusual request.
Access. Accounts, systems, logins, the phone number the answering service forwards to.
Context. Why you stopped using that supplier. What went wrong on that job. Why the process has that odd step in it.
The first four are recoverable with effort. The fifth mostly is not, and it is the one nobody thinks about.
Reduce the exposure before it matters
Document what only they know. Start with the highest-frequency work. The fast method is to have them narrate it while doing it and clean up the transcript.
Cross-train, genuinely. Not "shown once." Someone else does it, unsupervised, at least a few times, before it matters.
Own the accounts. Every account should be in the business's name with the business's recovery email. This is administrative and it is the thing that causes the worst chaos when it is wrong.
Own the relationships jointly. Customers should know at least two people. A second name on the account, an introduction, an occasional call from someone else.
Write down the context. Even a rough log of decisions and why. It feels pointless until the day someone asks "why don't we use them anymore?" and nobody knows.
Build systems, not dependence. The strongest version of this is that the thing does not need a specific person at all. See our note on the owner as the bottleneck — the same logic applies to every key role.
Do it now, not at notice
When someone resigns you have two weeks, they are checked out, and you are simultaneously trying to hire. That is the worst possible time to extract knowledge.
The right time is a quiet month when nobody is going anywhere.
Frame it honestly: this is not about you leaving, it is about you being able to take a holiday without your phone. That framing is true, and it makes the exercise something people cooperate with rather than resist.
If it has already happened
Move in this order:
- Access first. Accounts, logins, forwarding, anything that could lock you out. Change what needs changing and confirm you can get into everything.
- Anything time-sensitive that only they were tracking. Deadlines, renewals, commitments.
- Customers. Reach out proactively before they wonder. A named replacement, from a real person.
- Document as you rediscover. Everything you have to figure out, write down that day. This is the one chance you will get to capture it while it is fresh.
- Then fix the structural version so the next departure costs less.
The uncomfortable framing
A business where one person's departure causes a crisis is a business with a hidden liability on the balance sheet.
You would not run without insurance on the building. This is the same category of risk and most owners carry it uninsured for years because nothing has happened yet.