Such an image has been earned by its association with government, and also by the fact that in its treatment of agencies, COI has all the confidence you'd expect from its status as the country's biggest advertiser.
It's also a slightly outdated view, however. Carol Fisher, COI's previous chief executive, made great strides in modernising and improving the organisation.
Her successor, Alan Bishop, is now building on this. A year into the job and Bishop is putting into place a new structure that will see COI move towards the agency model. He's introducing a client services role (anyone interested in applying should turn to page 30 of last week's Campaign to see the job ad), and is also setting up a system that insiders are comparing to agencies' traffic departments.
There are two ways of looking at this. A former Saatchi & Saatchi executive, Bishop is using his learning from the agency world to improve on the unique structure of COI. That's the positive interpretation. The negative one is that his only experience is of adland so he has concluded that this is the right remedy to COI's perceived problems.
Bishop's greatest achievement so far has been to secure the return of the Department of Transport's business to COI. He is more mildly mannered than Fisher and it appears that some humble pie and astute negotiations have enabled him to fend off what was very recently a great threat to COI's future. His new restructure takes this further. He is acknowledging more strongly than ever that government departments are COI's clients.
Their patronage is not guaranteed, but the better their needs are anticipated and met by COI, the less likely they are to opt out.
This may be good news for government departments and it's probably good news for COI, but agencies, meanwhile, are greeting the move with caution.
The reason: they have their own account handlers.
Government clients will now have an agency account executive attempting to meet their needs while also looking after the agency's interests. They will also have a COI account executive attempting to meet their needs while looking after COI's interests.
Put more simply, COI is going to have more input into the end product, leaving agencies with less autonomy in the communications process.