The World Federation of Advertisers’ survey, run in partnership with The Observatory International, compared agency views with multinational clients across 12 sectors.
Just one in eight (12%) of brands said they provide separate briefs for each department or agency, half as many as three years ago when it was 24%.
However, 44% of clients are now briefing with a common master brief, and another 44% with a single brief for all stakeholders – both up from 36% and 40% respectively from the WFA’s last survey in 2014.
By contrast, agencies report too many briefs arrive with specific channels or outputs in mind – 59% said this happens "sometimes" and 39% "often".
The quality of briefs is also viewed differently by advertisers compared to agencies. 73% of brands said briefs include a single-minded proposition and single view of the consumer, compared to 76% of agencies that said these elements are either "sometimes" or "never" included in briefs.
The overwhelming majority of agencies said briefs lack a clear integrated customer journey. 93% said it is "sometimes" or "never" included.
71% of brands said they brief all departments and agencies at the same time, but just under a quarter of agencies (24%) said this happened "always" or "often".
Even if poor briefing by the client is acknowledged, the survey found it is still rare for agencies to charge additional fees for reworking responses – 12% of agencies do this. 51% of agencies said there is an additional charge when the brief is changed by the clients.
More people are now involved in creating briefs than in 2014. Clients said more external consultancies are being used (88% versus 47% in 2014), and more local marketers (65% versus 48% in 2014).
The survey questioned 32 multinational clients across 12 sectors with an annual spend of more than $14bn (£11bn) and compared 46 senior agency staff with global and regional roles.
Robert Dreblow, global head of marketing services at the WFA, said: "It would seem global brands are making progress in improving their integrated briefing process.
"Ultimately integration doesn’t come down to agencies or brands, it comes down to people. Strong client leadership coupled with agency collaboration is what’s needed to ensure consistency and improvement in applying these processes."