When someone asks this question in a seminar on blogging, then you know you have an intelligent audience of communicators. Indeed, looking at the programme, it seemed to be the only issue on the agenda at the IABC EuroComm conference in Paris last week (much more exciting than Les Blogs, I’m sure…)

As I sat through sessions with ROI in their title, I was struck by the difference Delahaye’s Mark Weiner highlighted between value and return on investment. To paraphrase (accurately, I hope), value is relative (or subjective) whereas return on investment is absolute (or objective).

If you accept this logic, then the way you measure relative and absolute metrics must also be different. You cannot apply a formula to tell you what value something has created for your organisation, and likewise you should not expect to be able to calculate ROI using subjective measures.

In an age when communicators still cannot measure traditional forms of PR and marketing properly, I later reflected why the lack of a blogging ROI measure would stop anyone from taking it seriously. My guess is that what they really meant was what’s the value of blogging?

And that – I believe – is a much easier question to answer. It just requires a body of evidence – a way of compiling and structuring the anecdotal stories we all read and hear from those who have experienced them. But we must also remember that value can be negative (it is relative, after all), and highlight those examples that go wrong.