The problem in this market is abundance, not scarcity. Several hundred firms can answer the same brief plausibly, and almost none of the signals that separate them appear in a credentials deck. A wall of masthead logos proves that a newsroom once carried a story. It does not tell you who pitched it, whether the relationship survived the placement, or whether the client paid for the slot.
London is several public relations markets wearing one label
Consumer publicity, corporate and financial communications, technology and business to business, and public affairs are separate trades. They involve different newsrooms, different rhythms, different sign off cultures and, crucially, different people. A firm with real depth in one is often a beginner in another, and nothing on the website will admit it. The generalist positioning is commercially sensible for the agency and expensive for you.
Decide which kind of public relations you are actually buying before you write a word of the brief. If your news is a funding round, a hire and a product roadmap, the useful contacts sit on technology and business desks and the work is largely written. If your news is a seasonal range and a founder with a story, the useful contacts sit on lifestyle and consumer desks and the work is largely visual, sample led and booked weeks ahead. Agencies that straddle both usually do so with two different teams, and you should ask which one you would get.
Ask who holds the relationships, not who holds the account
In public relations the gap between the people who win the business and the people who do it is wider here than in smaller markets, because the account director on stage has several pitches that week. Ask for the names of the individuals who would contact journalists on your behalf, how long each has covered your sector, and how many other clients they carry at the same time.
Then ask two questions that are harder to prepare for. Ask which publications they have never successfully placed in and why. Ask them to describe a story they tried to sell in the last quarter that nobody ran, and what they learned. Teams that do the work daily answer both without hesitation. Teams that outsource the calling to a junior will change the subject to strategy.
Retainers buy capacity, projects buy a defined outcome
A retainer is a standing claim on a team's time. A project is a finite piece of work with a date on it. Both are legitimate and they fail in different ways. Retainers fail quietly when your news flow dries up and you keep paying for a monthly report; projects fail when the launch slips and the fee has already been consumed by planning.
If you take a retainer, get the monthly fee expressed as an hour allowance with a written rule about what happens to unused time and what triggers an overage conversation. Ask what the team does in a month when you genuinely have nothing to announce, because the honest answer, which is proactive commentary, journalist meetings and building material for later, is very different from filling the calendar with awareness days.
Earned coverage, paid placement and the grey strip in between
Ask every candidate to label each item in their coverage sample as earned, paid or contributed. Plenty of respected titles now sell sponsored features and commercial partnerships, and a growing number accept contributed bylines through commercial teams rather than editors. None of that is dishonest, but it changes the cost of the result and it changes how a reader weighs it.
The reason this matters commercially is simple. If half the coverage in a case study was bought, the agency's public relations skill is not what produced it, and your budget will need the same media spend again next time to reproduce the effect. Get the split in writing before you compare two proposals that look similar.
Measurement that survives a conversation with finance
Agree the scorecard before signing, not at the first quarterly review. Advertising equivalents are the wrong instrument and most serious buyers have abandoned them. What holds up is a small set of measures: share of voice against a named competitor set, whether your actual messages appear in the copy rather than just your name, the quality and relevance of the outlets, referral traffic from coverage, and movement in branded search over a quarter.
Insist that at least one measure connects public relations activity to commercial reality. If nobody in the room can name the number that would make you renew, the reviews will be a slideshow and the relationship will end on a feeling.
Crisis cover is a separate purchase and most briefs forget it
Reactive work is where public relations earns its keep and where retainers are most often silently exhausted. Establish who answers the phone at eight on a Sunday evening, how fast a holding statement gets drafted, who has authority to approve it on your side, and whether those hours come out of the retainer or arrive as a separate invoice.
Ask whether they have run a rehearsal with a client, not merely written a plan. A plan that has never been tested tends to collapse on the first detail, usually the one about who is allowed to speak. Spokesperson training belongs in the same conversation: the person who fronts a difficult story should have practised before the story exists.
What you keep when the relationship ends
Three clauses decide whether a public relations engagement leaves you stronger or dependent. The first is the media list and the press office archive: ask whether you receive the contact record, the approved boilerplate, the message house and the coverage log on exit. The second is conflict of interest, since the same team may be pitching a direct competitor to the same journalist, and you want that named and restricted rather than discovered.
The third is notice. Three months is common and it is the single largest hidden cost of a mismatch, so negotiate a short initial term with a review date rather than arguing about notice later. Add licensing for any photography, film or research the agency commissions, because assets you cannot reuse in advertising are worth far less than they cost.
Getting from a long list to three comparable public relations proposals
Write one brief, send it out unchanged, and require the same headings back from everyone: sector experience, named team, media approach, measurement, reactive cover and commercial terms. Real differences will then show up where they belong, in judgement and in access, instead of in each firm's decision about what the job was. If you would rather write it once and collect structured replies, you can set out the requirement and compare responses side by side.
Where the underlying need is discoverability rather than reputation, start with search specialists working in the same market; where it is community and always on publishing, look at content marketing firms. Buyers planning a national programme often shortlist alongside teams covering the wider country, and campaigns that hinge on product film usually need a motion and animation studio in the same brief. For the full category and every market it covers, begin with the overview of public relations agencies.