Most agencies don’t fail because they lack capability. They fail because they received a brief that didn’t give them what they needed to succeed.
A vague brief produces vague work. A brief that defines the wrong success criteria produces work that hits the wrong target with precision. And a brief that leaves strategic decisions to the agency — decisions that should have been made by the client — produces an agency that’s guessing at what you actually want.
Writing a good brief is one of the highest-leverage things a marketing leader can do. Here’s what it requires.
What a Good Agency Brief Contains
The Business Context, Not Just the Marketing Objective
Most briefs start with the marketing goal: we want X leads, Y awareness, Z engagement. That’s the destination. What’s missing is the context that helps an agency understand why this campaign matters, what’s at stake, and what the broader business environment looks like.
Share the board-level pressure. Explain the competitive dynamic. Describe what success would mean for the business — not just for the campaign. Agencies with that context make decisions differently than agencies working from a deliverable list.
A Specific, Measurable Success Definition
“Drive awareness” is not a success definition. “Generate 150 MQLs at a CPL below $200 within 90 days, with at least 20% converting to SQLs within 30 days of lead capture” is.
The more specific the success definition, the more useful the brief — and the more accountable the agency can be held to it. Vague success definitions give everyone cover. Specific ones create clarity.
The Audience, Defined Beyond Demographics
Most briefs describe the target audience demographically: CMOs at B2B companies with 100+ employees. That’s a starting point, not an audience definition.
A useful audience definition includes what that person is worried about right now, what they’ve tried before that hasn’t worked, what they believe that might be wrong, and what would make them trust a new vendor enough to have a conversation. That level of specificity changes the creative and the channel strategy — not just the targeting.
The Non-Negotiables and the Openness
Be explicit about what is fixed and what is open to the agency’s judgment. Fixed: the offer, the timeline, the budget, the brand standards. Open: the creative approach, the channel mix, the messaging angle, the content format. Agencies that don’t know what’s flexible default to safe — and safe rarely produces great work.
What Not to Do
A brief that defines what to avoid is as useful as one that defines what to achieve. If a tone has been tried and failed, say so. If a channel is off-limits, say why. If there’s a competitor whose approach you explicitly don’t want to emulate, name them. Negative definition is underused and undervalued.
The Brief Review That Changes the Output
After the agency receives the brief, ask them to play it back before they start working. Not the deliverables list — the strategic understanding. What do they think you’re trying to accomplish? Who do they think you’re talking to? What do they think success looks like?
The gaps between your intent and their understanding, surfaced in that conversation, are the gaps that would have produced disappointing work. Closing them before execution starts is infinitely cheaper than revising after the fact.
Frequently Asked Questions
How long should an agency brief be?
Long enough to provide genuine context — short enough to be read. Most well-written briefs fit in one to three pages. A brief that requires ten pages to communicate the objective is usually a brief that hasn’t been edited enough. The discipline of writing a tight brief forces the clarity of thinking that produces better work downstream.
Who should write the agency brief?
The marketing leader who owns the program — not delegated to a coordinator or written collaboratively by committee. The brief should reflect a clear strategic point of view, which requires someone with the authority and context to make strategic decisions. A brief written by committee typically reflects everyone’s input and nobody’s judgment.
What happens when the agency delivers work that doesn’t match the brief?
Start by assessing whether the brief was clear enough to produce the expected output. If it was, the agency has a performance issue — address it directly and specifically, with reference to the brief criteria the work didn’t meet. If the brief was ambiguous, that’s a shared problem — revise the brief together and reset. The brief is the accountability document. Both parties need to own it.
Should the agency contribute to the brief, or just receive it?
The best briefs are informed by agency input before they’re finalized. Share the business context and the preliminary objective, invite the agency’s strategic perspective, and use that input to sharpen the brief before finalizing it. An agency that brings insight at the brief stage — rather than waiting to be handed a finished document — is operating strategically. That’s the relationship worth having.
The Brief Is the Relationship
How you brief an agency reflects how you want to work together. A brief that shares real context, defines success specifically, and is open about constraints invites the agency to operate as a strategic partner. A brief that’s a deliverable list invites them to be an execution shop.
Most agencies will operate at the level you set. Set it deliberately.
About the Author
Kalina Totzeva is a Marketing Manager at DSM, a full-service digital marketing agency based in New Jersey. She manages integrated marketing programs for clients across New Jersey and nationally, with hands-on experience across social media, content, paid media, and account strategy. Kalina’s work is built around one objective: finding the opportunities inside a client’s marketing program that translate directly into growth. She brings a full-picture perspective to every account, connecting channels, strategies, and data into programs that produce results clients can see and measure.