Figures released last week show the Government is now by far the largest advertiser in the UK.
It spent £211m of its £540m marketing communications budget on advertising in 2008/09, a 35% increase on the previous year, and forged ahead of the other two biggest spenders - Proctor & Gamble and Unilever. Campaigns on obesity, road safety, smoking and climate change were just some of the areas driving this.
But government advertising divides opinion profoundly. Exponents of advertising must surely be in favour, especially at the COI's roster of media agencies: MediaCom, Carat, Starcom, I-Level and Posterscope. After all, advertising works doesn't it? And the Government claims to have saved £241m in media costs against "recognised benchmarks" in 2008/09, a near 50% reduction.
On the other hand, there is built-in suspicion of government intervention in the media sector, epitomised by attitudes to the BBC and its operation in markets that prevents commercial players from competing properly.
The COI's "recognised benchmarks" turn out to be TV station average, Radio Advertising Bureau estimates, and press, cinema and out-of-home rate cards - although any self-respecting media trader would consider those as just starting points for negotiation. Now the COI plans to rationalise its media agency roster to create greater efficiencies.
In its annual report, COI evidence suggests advertising does indeed work. It claims its tax campaign has saved HM Revenue and Customs about £185m, an ROI eight times its ad investment. And the £21.4m spent on ads by the Home Office on vehicle crime reduction has reduced the cost of crime by £590m. The COI says it is supporting the creative industries and expects demand for its services to remain high in 2009/10 - provisional budgets have been set at similar levels to last year.
Last weekend, Tory leader David Cameron told the aforementioned BBC there was a "huge amount of waste and bureaucracy" to be tackled across Whitehall and put government advertising squarely in the frame.
But if the COI's ROI figures are to be believed, and if the Tories believe in the power of advertising, Cameron should think twice about cutting the COI's budget if he gets into power at the next General Election.