Is PR really difficult to measure?

I'm in Madrid for AMEC's annual European summit. It's hot, nice and hot! PR people seem to have grasped the evaluation baton in recent years. Due partly to the good work of AMEC, the subject of measurement is no longer an afterthought in campaign planning. When I talk to in-house directors of comms, they broadly sit in one of two evaluation camps: 1. "Yes we need to improve our evaluation. I'm on the case and we should have a pretty robust process within 12/18 months" Or 2. "Yep we've got an evaluation/early warning system in place. It's not perfect but it works. It's plugged into all our media channels and works internationally (if relevant)." My non-scientific straw poll puts the percentages at about 40 per cent are content with their evaluation process and 60 per cent say it needs work. Now, whilst I'm not saying we've reached some sort of PR evaluation utopia, I do think the reality that circa 40 per cent of corporates have a robust PR evaluation model means that public relations needs to stop its paranoia about measurement. McClaren Automotive's marketing director David Brimson summed it up perfectly for me, when at our recent PR Analytics conference, he stated that he didn't believe that it was more difficult to measure the impact of PR than advertising – or indeed any other part of the marketing communications mix. The next two days will tell me whether PR's measurement debate is growing up or whether the sector's insecurity still dominates this debate.