Power can be an ephemeral thing and the task of choosing the 50 communicators who wield the most of this elusive quality for our annual Power List is one that inevitably leads to intense debate inside and outside of PRWeek Towers.
The definition of what power means differs from individual to individual. It can be exerted in many different ways: from the vista of an in-house communicator at a large corporation, the boss of a top 10 PR agency, or a player in the viper's nest that is the DC political scene.
Then there are the fire-starters at innovative small businesses, agencies, and nonprofits that are destined to become the Facebooks, Edelmans, and Bill & Melinda Gates Foundations of the future - their significance is catalytic rather than monolithic, but no less influential for that.
Let's be frank: it is impossible to create a definitive list without excluding some extremely credible individuals who have compelling arguments to be a part of the PRWeek annual elite.
But there are some people who simply have to be on the list, and our number one this year, Jon Iwata, definitely comes into that category.
The IBM stalwart is setting the template for what a modern communications and marketing function should look like, both from the perspective of his own company and as chair of the Arthur W. Page Society, where he leads an initiative to spread the new model of corporate communications across all companies.
He is a truly inspirational figure to everyone in the PR community, as I'm sure the 49 exceptional individuals who join him on our Power List would agree.