There's nothing worse than a co-worker who spouts moral imperatives on a daily basis but fails to practice what they preach.
We all know one - a renewable energy chief executive who drives a gas guzzling 4x4 car, or a communities minister who eats more than their fair share of the world's dwindling food supplies.
Which is why the Sceptic Tank was delighted to see PUMA chief Jochen Zeitz and green accounting partners at Trucost donning leather-free trainers to present the company's new environmental profit and loss statement.
Admittedly, the Tank was at first shocked to think that Zeitz had made a fashion faux pas by pairing sneakers with a suit, but we breathed a sigh of relief when it was explained that the panel were simply showing off PUMA's green credentials in action.
However, if you look closely at the photo you will notice an odd one out. While PUMA managed to convince Trucost that sneakers and suits are very much this season's look, PwC's Alan McGill stuck to his black office shoes.
The firm's sustainability partner jokingly suggested his job was too dull to warrant a jazzy pair of sneakers.
But a spokeswoman later told us that due to various rules that only accountants would understand PwC can't be seen to be promoting their clients products in any way.
Although the Tank remains confident PwC's sustainability team each keep a pair of leatherless trainers for the weekends.