Why does advisory work start in writing?

What does the engagement letter record?

Five things, every time. The client's question in plain words. The deliverables the firm will produce. What is outside scope. The fee basis. And the responsibilities: who reviews, who approves, and who the client should expect to hear from.

Take our tax advisory engagement for Halden Foods, which is matter 2041 in our records. The letter says the firm will review the qualifying equipment schedule, prepare a written advisory memo and attend one board preparation call. It says that a filing service, litigation advice and a general audit are outside scope. It names the fee basis as a fixed fee for those deliverables. It names Rohan Mehta as the reviewer of the technical memo and me as the approver of any scope change.

That is a short document. It is also the document the whole matter rests on.

Why is a request on a call not a change of scope?

Because the person on the call is rarely the person who can agree a change, and the moment of the call is rarely the moment to price one. When a client director asks an associate for an extra equipment model, the associate's job is to acknowledge the need, say what the signed letter covers, identify what would change, and close with an owner and a date for an answer.

Our methods handbook puts it in one sentence: a request made during a call is not permission to expand scope. It is recorded as a proposed change for the engagement partner. The change is then agreed in writing, with fee, timing and reviewer, before work begins.

This protects the client as much as the firm. A client who gets an unpriced favour today gets an unexpected invoice later, or a deliverable nobody reviewed.

What does the written change contain?

The same five things as the letter, in miniature. What is being added, what it costs, when it will be delivered, who reviews it, and who at the client agreed to it. If any of the five is missing, the change is not agreed yet.

What goes wrong without the letter?

Three things, and we have seen all of them at other firms.

• The scope drifts. Each small request looks reasonable on its own. Ten of them later, the matter is twice the size and nobody can say when that happened.
• The commercial terms get remembered instead of read. An associate quotes a standard payment period from memory when the letter says something else. For Halden, the letter says a deposit of 25% on signature and payment net 21 from the invoice date. Those are the terms that govern, not a default.
• Responsibility blurs. When nobody is named as reviewer, everybody assumes someone else read it.

How does the letter connect to the rest of the method?

The letter is the first of four written steps. Conflicts clearance comes before it; June Okafor runs the intake and I record the clearance decision before a matter number is issued. Capacity confirmation comes after it; June checks the staffing plan against the statement of work before anyone is booked. Then the work and its review. The exam our associates sit asks them to put those four steps in order, because the order is the method.

What should a client expect from us?

A letter before work, a written change before more work, and an invoice that matches both. If you ask for something on a call, expect to hear "here is what the letter covers, here is what would change, and here is when you will have an answer." That sentence is not a refusal. It is the firm doing the first part of the job properly.

What should a new associate take from this?

Three habits. Read the letter before the first piece of work on any matter, and read it again before any conversation in which the client might ask for more. Carry the five recorded items in your head: the question, the deliverables, the exclusions, the fee basis and the responsibilities. And when a request arrives that the letter does not cover, treat it as the start of a short written process rather than a test of your willingness to help.

None of this makes the firm slower in any way the client would notice. A written change on the Halden matter takes less time to prepare than the extra modelling itself would, and it arrives with a fee and an owner attached. What the client notices is that nothing promised on a call later turns out to be unpriced, unstaffed or outside the work they agreed to. That is what the letter buys, and it is why the work starts in writing.

Q&A

The questions clients and new associates ask most about engagement letters are answered below.

Last updated 1 October 2026.