How to write a corporate event brief an agency can quote on accurately

When three agencies return quotes that differ by a factor of two, the usual assumption is that one of them is overcharging. More often, each has quoted a different event, because the brief left enough open that each agency filled the gaps its own way. One assumed a hotel ballroom, another a convention centre; one priced a custom set, another a standard truss stage.

A good brief doesn't need to be long. It needs to close the questions that change the number, and say plainly which ones are still open, so that every agency is answering the same question.

• The objective — what should be different a week after the event. This decides the format, and the format decides most of the cost structure.
• The audience — headcount, who they are (employees, dealers, clients, industry), the seniority mix, and where they're coming from. Travel from several cities changes the brief entirely.
• The date window — a fixed date, a preferred month, or a range. Say which, because a fixed date in peak season is priced differently from a flexible one.
• The budget — a number or a range. This is the one most often left out; more on it below.
• Venue status — secured, shortlisted or open. If it's secured, name it and attach the floor plan and technical details if you have them.
• Deliverables — stage and set, AV and LED, content capture, hospitality, travel and stay, talent. Mark each as required, nice to have, or not needed.
• Open decisions — anything leadership hasn't settled yet, such as whether there will be an awards segment or whether the event goes hybrid.

Withholding the budget is the most common brief mistake, and it's usually done with good intentions: to see what agencies propose without an anchor, or to avoid being upsold. In practice it produces proposals built around what each agency would like to sell, which you then have to negotiate backwards from.

A range works as well as a number. It tells an agency whether it should be designing a hotel conference with a standard stage or a fabricated set with multi-camera capture, and it means the proposals come back comparable instead of spread across three different levels of ambition.

• Brand guidelines, and any event identity that has already been designed.
• Last year's event, if this one recurs — photos, the run sheet, and what didn't work. What didn't work is the most useful thing you can send.
• The venue floor plan and technical specifications, if the venue is secured: ceiling height, rigging points, power and load-in access.
• An attendee profile — roles and seniority rather than names — so seating and hospitality can be planned sensibly.
• Compliance requirements, if any: content review for regulated sectors, vendor onboarding paperwork, insurance certificates.

A brief is the start of a conversation, not a specification to be priced in silence. If an agency returns a quote without asking a single question, it has filled every gap with an assumption, and that is exactly what makes quotes impossible to compare.

Expect questions about who signs off decisions and how quickly, about load-in and rehearsal time at the venue, about what happened at last year's event, and about the one thing that absolutely cannot go wrong. The answers shape the proposal more than the brief itself does.

If your brief is only half formed, send it anyway. We would rather work through an incomplete brief with you than quote against guesses.