Marketing Brief: How to Brief a Consultant or Agency

Most owners write the brief after they have chosen who to work with, if they write one at all. It gets said out loud in a first meeting, both sides nod, and everyone leaves with a slightly different version of what was agreed.

I have been handed hundreds of briefs across 13 years in marketing, and I have written a few weak ones myself early on. The work was rarely the problem. The instruction was.

A marketing brief is the cheapest quality control available to a business buying outside help. Half an hour of thinking, no cost, and it decides whether the next three months produce something useful or a polite disagreement about what was promised.

What a Marketing Brief Actually Does

The decision it forces you to make

A brief forces one decision before any work starts: what outcome you are buying. Not a channel. Not a set of deliverables. The result that has to be true for the spend to have been worth it.

That is why briefs feel uncomfortable to write. It is easier to ask for more leads from Google than to state which enquiry type is worth paying for, how many you need, and what you will do with them when they arrive. The vague version feels safer because it cannot be wrong, and it also cannot be measured, which is the same thing.

Write the outcome first and the rest gets easier. Everything after it either supports that outcome or is decoration.

What it is not: a contract, a channel plan or a wish list

Three documents get confused with the brief, and mixing them up is why projects start badly.

The scope of work lists what will be delivered, when, for how much and by whom. The channel plan and the strategy set out how the work will be done. The brief sits above both and explains why the work exists at all. The wish list is the one to watch, because it reads like a brief, it runs to four pages, and it carries five objectives that cannot all be first priority.

If your document explains tactics and never answers why, it is a channel plan wearing a brief's clothes. Fix that before it reaches anyone.

Why Poor Briefs Waste Money and Time

What the research found about brief quality

The strongest evidence on this comes from the BetterBriefs Project, which the Institute of Practitioners in Advertising published. The IPA describes the scale of it in one line: "The survey is the largest ever done on this topic representing the opinions of over 1700 marketeers and agency staff from over 70 countries."

The gap it exposes is not small. "Marketers (80%) think they write good briefs, and only 10% of creative agencies agree." The disagreement runs through every measure the research took. "Over three quarters of marketers (78%) think the briefs they write provide clear strategic direction, with only 5% of creative agencies agreeing." Both sides do agree on one thing: "Marketers (89%) and agencies (86%) agree that it's challenging to produce good creative work without a good marketing brief."

Then there is the cost. "Respondents estimated that a substantial 33% of the marketing budget goes to waste due to poor briefs and misdirected work." Read that as a range rather than a precise accounting, because it is an estimate from the people closest to the work, and it is the number I would put in front of any owner who thinks the brief is paperwork that can be skipped.

There is market context on the same theme in Search Engine Journal's analysis of how brands are rethinking agency relationships. It reports cost as the main driver of change, with 83% of brands citing cost efficiency as the key reason for expanding their in-house teams, and it cites a 2024 report in which 40% of companies surveyed said they were likely to switch from their primary agency in the next six months. Both figures are reported there rather than measured independently, and both point the same way: the tolerance for work that misses the mark is lower than it used to be.

The rebrief cycle and what it really costs

"And rebriefs happen too often with marketers (69%) and agencies (73%) agreeing, leading to loss of time, money and fueling frustration on both sides."

A rebrief is expensive in a way that rarely shows up on an invoice. The first round of thinking has already been paid for and thrown away. The second attempt usually starts from a defensive position on both sides, with the agency guessing at what was really wanted and the owner checking every decision against a definition that only exists in their head. Meanwhile the calendar keeps moving, and in retail or seasonal work the window that mattered closes.

The cheapest intervention available is thirty minutes with a blank page before the first meeting. Nothing else on this list returns as much for the effort.

The Six Sections Every Brief Needs

Six sections, one page, and no more. Adding sections is how a brief turns into a document nobody reads to the end.

The problem in one paragraph

State the problem in your own words, not in industry language. Enquiries are down but the ones coming through are the wrong fit. We sell to facilities managers and nobody in that role knows we exist. Our best customer type has stopped calling. If you cannot write the problem in one paragraph, you do not have a brief yet, you have a feeling, and feelings do not survive contact with a scoping conversation.

The audience and what you know about them

Name the buyer, their role and what usually triggers the purchase. Then add what you already know: the questions your sales team hears, the objections that come up twice a week, the customer type that turns out to be more trouble than they are worth.

What you know from the sales conversation is evidence the consultant cannot get from a keyword tool. Hand it over. It is worth more than any competitor analysis you could pay for.

One objective and the measure that proves it

One objective, tied to a number you can already see in your own reporting. Not two, not four. If everything is a priority then nothing is, and the consultant will pick the one that is easiest to report on rather than the one that matters most to you.

Write the measure in the same line as the objective, and choose it before work starts rather than in week six. If you cannot state how you will know it worked, the objective is not finished.

Scope, deliverables and timing

Say what you expect to exist at the end of the engagement and roughly when. You do not need to design the campaign, that is what you are buying, but you do need to say whether you want strategy, execution, or both, and whether there are dates you cannot move, such as a product launch or a seasonal peak.

Budget range and who decides

Give a range with the reasoning behind it. A brief with no budget tells a consultant nothing about scale, so you will get proposals built around an imagined number, and you will not be able to compare them honestly.

Say whether the range covers media spend, fees, or both, and name the person who signs off. If two people can veto the budget, say so at the start rather than at the proposal stage.

The constraints and what must not break

List the things that cannot change: brand guidelines, a platform decision, a supplier agreement, a legal requirement, a promise already made to customers. Constraints are not obstacles to good work, they are the edges that make a plan realistic. A consultant who ignores them will hand you something you cannot use.

Write the Brief Before You Shortlist Anyone

Why the brief is your selection tool

Most owners write the brief after choosing a partner, which makes it a formality rather than a test. Written first, it does something more useful: it shows you how each candidate thinks.

Give two or three people the same brief and you will get two or three different readings. One will restate your problem and propose a path. One will offer a menu of services. One will ask a question that exposes a hole in your own thinking. That last response is worth paying attention to.

The questions that expose a weak brief in a meeting

A good consultant will ask why this objective, how you will measure it, and what has already been tried. If those questions cannot be answered from your one page, the brief is not done.

If nobody asks anything, be cautious. Either the brief was so complete that no question survived it, which is rare, or the proposal is being built to a template rather than to your business.

A One Page Brief Template for an Australian Owner

Filling it in honestly in 30 minutes

Set a timer for thirty minutes. Write the six sections as sentences, not bullet points, in the order they appear above. Then stop and read it back as though you were the person receiving it, and check whether you could deliver what you have asked for with the budget you named.

If the honest answer is no, the brief has just saved you a quarter. Adjust the objective or the budget before you send it, not after the first proposal lands.

The three lines owners most often get wrong

The objective line, because it lists channels instead of an outcome. The measure line, because it is written after the fact. And the budget line, because owners say they will discuss it later and then compare quotes that were priced against three different scopes.

Those three lines decide most of what follows. Get them right and the rest of the page takes care of itself.

Briefing Mistakes That Cost You the Most

Vague objectives and hidden agendas

More leads is not an objective. It is a direction, and it hides the real one, which is usually a specific number of a specific enquiry type by a specific point in the year. An unstated agenda, such as wanting a proposal that justifies a decision already made, is worse because nobody can design against it.

Leaving the measure until week six

Choosing the measure late is how a good month gets reported as a bad one, and how a bad month gets reported as a good one. Decide it in the brief, then leave it alone. Changing it halfway through is how trust between an owner and a consultant breaks.

Changing the goal mid engagement

Businesses change. A product line gets pulled, a competitor moves, a new opportunity appears. Changing the goal is allowed. Changing it in conversation without writing it down is what turns a working engagement into a rebrief, and the research above is clear about how often that happens.

Write the change, restate the measure, agree the date. It takes ten minutes and it protects both sides.

What to Expect Back From a Consultant or Agency

The response a good brief should produce

A written response that restates your problem in their words, names the approach and why it fits your situation, states what they will need from you, and puts a number on it. If the response could have been sent to any business in your industry, the brief was not read carefully, or the response was written before it arrived.

Expect also a view on what you left out. The most useful reply I can give an owner is that the objective they wrote cannot be measured with the reporting they currently have.

Red flags in a proposal that ignores your brief

A proposal that answers a question you did not ask, quotes deliverables you never mentioned, or promises an outcome you set as unmeasurable. Any of those means the brief was treated as background reading.

If you want to see how brief led work runs inside a firm, how these engagements look in professional services is a fair read. If you are still deciding who should sit at the other end of the brief, the difference between a consultant and an agency is worth ten minutes before you shortlist.

Keeping the Brief Alive Through the Engagement

The review cadence and the written change rule

The brief is a live document, not an attachment in a shared drive that nobody opens again. Review it at an interval you agree at the start, monthly for a first engagement, and check two things: whether the objective still matters, and whether the measure is still the right one.

Any change to either goes in writing and both sides acknowledge it. That single rule prevents most of the resentment that builds in the final weeks of a project, when the work is delivered against a brief that only one side remembers.

Turning an Approved Brief Into a Plan

The step from brief to strategy document

Once the brief is agreed, the work becomes straightforward. A strategy document takes the objective and sets out the channels, the sequence, the effort and the budget split, then hands that over for implementation.

That is the point where turning a brief into a marketing strategy that fits your business starts, and it is much easier with one objective written down than with four remembered across three meetings.

Diarising the first check in

Put the first review in the calendar the week you sign, not the week you start wondering how it is going. Bring the number you named in the measure line, in whatever form it exists, and be honest about it. Early honesty is cheap. Late honesty is a rebrief.

Owner questions I get asked before a brief is written are collected on the questions page, and they are a reasonable place to start if the blank page is winning.

Marketing Brief FAQ

How long should a marketing brief be?

One page is usually enough for an owner working with a consultant or a small agency, because every extra page adds a section nobody reads. The BetterBriefs research that the IPA published found marketers and agencies disagree sharply about brief quality and that rebriefs are common, with 69% of marketers and 73% of agencies saying rebriefs happen too often. A tight one page brief that states the problem, the audience, one objective and the measure beats a long document with five objectives.

Should the brief include the budget?

Yes, as a range and with the reasoning behind it. A brief with no budget tells a consultant nothing about scale, so you get proposals you cannot compare, or proposals built to an imagined number that does not exist. State the range, whether it covers media spend, fees or both, and what would have to be true for the top of that range to be justified.

Who should write the brief?

The person who owns the result, not the person who manages the relationship. If the brief is written by a coordinator without access to the commercial goal, it will describe tactics rather than an outcome, and the work will drift. If the owner is not writing it, they should be the one signing it off line by line.

What is the difference between a brief and a scope of work?

The brief explains why the work exists and what success looks like. The scope lists what will be delivered, when, for how much, and by whom. You cannot write a good scope without a brief, because you would be pricing activity with no agreed outcome. The brief comes first, and it stays live for the length of the engagement.

What should I do if the consultant suggests changing the brief?

Take it as a good sign, provided the suggestion is written and tied to evidence. A consultant who has done this before will often see a faster path to the same outcome, or spot that the stated objective cannot be measured with your current setup. Agree the change in writing, restate the measure, then continue. Silent drift is what turns a good engagement into a rebrief.

Can a brief stop a project going off track later?

It gives you a written reference point, which is most of the value. When a project goes sideways it is usually because the goal changed in conversation and nobody wrote it down. Keep the brief open, review it at an agreed interval, and treat any change to the objective or the measure as a formal change you both acknowledge.