There’s already a back and forth going on about the business mission Mayor Gregor led to London recently, but here’s the story I wrote, belatedly.

These kinds of missions are becoming more popular among the mayoral set, it seems to me. This is Gregor’s second. Surrey Mayor Dianne Watts led one to India not too long ago. It appears to be part of a world-wide trend to connect more city to city, which is the way some economists think the world’s trading systems really work.

But these efforts are difficult to judge, since cities can’t offer the kind of tax credits or other incentives that a federal or provincial government can. And how do we judge their results? If a mayoral mission goes over and gets deal signed while there, it seems as though the actual trip was just for show because surely no company decides on the spot to commit to a complex and expensive deal. But if there are no deals or announcements made for months, how are we to judge whether the actual trip had anything to do with the ultimate results?

Obviously, business people think these trips are worthwhile because they keep pushing for them and are willing to pay their own way to go along. (That was the case with both Robertson and Watts.) But how shall we measure their cost-to-benefit ratio and success?