Explain the decision context
Open with a concise account of the organisation, offer, audience and event that triggered the search. Explain why an external agency is needed and who owns the outcome. Agencies need the context that changes their recommendation, not a long corporate history copied from another document.
Name the decision-makers, contributors and final approver. If procurement, legal, technology, sales or other teams can affect the work, make those dependencies visible. A clear governance picture helps suppliers plan workshops, reviews and realistic timing.
Put this into practice
- What changed or created urgency?
- Why is agency support needed?
- Who owns the outcome and budget?
- Who contributes, reviews and approves?
- Which existing partners or systems matter?
Define the problem, audience and outcome
Describe the observable business or audience change required. Add the evidence you already have, known barriers and assumptions that still need testing. Avoid presenting a channel or deliverable as the problem; a request for a campaign, website or search program should connect to a reason that work is needed.
Prioritise audiences rather than treating every group as equally important. Describe useful measures as a hierarchy: business outcome, audience behaviour, channel contribution and diagnostic signals. Be explicit where product, pricing, sales, operations or other factors share responsibility for the result.
Put this into practice
- Problem stated without assuming the solution
- Priority audience and required behaviour
- Current evidence and baseline limitations
- Desired outcome and decision measures
- Assumptions the agency may challenge
Set scope boundaries and responsibilities
List capabilities and outputs you believe are needed, while inviting agencies to challenge the mix. Separate mandatory deliverables from optional ideas and distinguish launch work from ongoing service. Include volumes, channels, markets, formats and review cycles where they materially affect effort.
Show the division of work between the agency, your team and other suppliers. Clarify who provides content, data, technology access, subject-matter expertise, approvals and implementation. Comparable quotes depend on suppliers pricing the same responsibilities.
Put this into practice
- Required capabilities and outputs
- Mandatory, optional and out-of-scope items
- Expected volume, frequency and markets
- Agency, client and third-party responsibilities
- Handover, training or ongoing support needs
Tell agencies how to respond and how you will decide
Request a response structure that supports fair comparison: diagnosis, recommended approach, named team, scope, plan, evidence, costs, assumptions, client responsibilities and risks. State the timetable, presentation format, clarification process and contact point. Give every participant access to material changes or answers where appropriate.
Publish the criteria and distinguish pass-or-fail conditions from weighted preferences. Explain what useful evidence looks like and who will evaluate the response. Agencies can then focus effort on the decision instead of guessing which presentation style will appeal to the panel.
Put this into practice
- Required response headings and attachments
- Proposal and presentation timetable
- Clarification and communication process
- Evaluation criteria and weights
- Mandatory conditions shown separately
Run a final usability check
Ask a colleague who was not involved in writing the brief to explain the problem, priorities, constraints and decision process after one read. Any material point they cannot find quickly may also be missed or interpreted differently by suppliers. Move supporting detail to appendices if it obscures the core decision.
Check the brief for contradictions and inherited requirements from earlier projects. Remove requests that cannot affect selection, explain specialist language and make document versions clear. A good brief is not the longest document; it is the one that helps capable agencies make informed choices.
Put this into practice
- Priorities can be understood after one read
- No material contradiction between scope, budget and timing
- Specialist terms and abbreviations explained
- Appendices clearly linked to the main brief
- Version, owner and response deadline visible
Common questions
How long should an agency brief be?
Use the length needed to make the decision context, priorities, scope and constraints clear. A concise main brief with structured appendices is often easier to use than one long document with no hierarchy.
Should the brief prescribe the solution?
State mandatory outputs and constraints, but distinguish them from assumptions the agency may challenge. Explain the outcome and evidence behind your proposed solution so suppliers can recommend a better route when justified.
Can the same brief be sent to every agency?
Yes. Every participant should receive the same core requirements and material clarification answers. Tailored conversations can explore each agency's approach, but the underlying decision should remain comparable.