There is a particular kind of Monday where someone walks in, tells you they are done, and leaves that day. No two weeks. No handoff document. No walkthrough of the work in flight.
If it has not happened to you yet, it will. And the reason it hurts more than it should has very little to do with the person leaving.
The first mistake is trying to replace the person
The instinct is to open a job posting that afternoon. Resist it for about a week.
You do not yet know what you are hiring for. What you know is the job title they held, which is rarely the same thing as the work they were actually doing. In a small business, roles drift. People pick up whatever is broken and never write it down. The person who left as a senior project manager may also have been the only one who knew how the billing export worked, who your best subcontractor's cell number belonged to, and which client wants a call rather than an email.
Post too early and you will hire for the title. Then you find the gaps in month three, and you are recruiting again.
Do these four things first
Find the work in flight, not the files. Go to the people who were waiting on them. Clients, vendors, the rest of your team. Ask one question: what were you expecting from them this week? That list is more accurate than anything you will reconstruct from a laptop, and it is the list that will cost you money if you miss it.
Close access the same day, and write down what you closed. Email, payroll, the bank, the CRM, the project system, the shared drive, building keys, anything with a password. You are not expecting bad behavior. You simply cannot show later that you did it properly if you did not keep a list. This is the part owners skip and regret.
Decide what genuinely cannot wait. Most of what feels urgent in week one is not. Payroll, a client deliverable with a date on it, and anything with a legal or filing deadline are real. Almost everything else can absorb two weeks of slower.
Write the job down before you write the job posting. An honest list of what that person actually did, gathered from the people around them, is the single most useful artifact to come out of a bad departure. It tells you whether you are hiring one person or two, whether half of it should be split across the team, and whether part of it should not exist at all.
The part nobody wants to hear
A departure with no handoff is not really a people problem. It is a systems problem that was always there, and the departure is just the first time you could see it.
If one person leaving takes the knowledge with them, that knowledge was never in the business. It was on loan. That is true whether they gave you two weeks or two hours, and a two week notice period mostly buys you a hurried document that nobody reads again.
The fix is unglamorous and it works: write down how the recurring things get done, while the person who does them is still here and not annoyed with you. Not a binder. Not a process improvement initiative. One page per recurring task, written by the person who does it, kept somewhere findable. Do the two or three that would hurt most to lose, then stop. You are buying insurance, not building a manual.
Most owners get to this only after a departure like the one above. That is normal, and it is not too late. The week after a resignation is actually the easiest week you will ever have to justify spending time on it, because everyone in the building just felt the cost.
Where to start
Pick the one role where a sudden exit would hurt worst. Probably not the newest person. Probably the one who has been there longest and never complains. Ask them to write down the three things they do that nobody else knows how to do.
You will learn something uncomfortable, and you will be glad you learned it on a Tuesday rather than on a Monday like the one at the top of this page.
If your business is carrying a departure right now and you want a second set of eyes on what to cover first, reply and tell me the shape of it. Happy to think it through with you, and happy to be told I have the priorities in the wrong order.
M7 Fractional is not a law firm. Anything touching final pay timing, separation agreements, or a dispute should go to qualified counsel before you act.