Sometimes other people you work with suck. You know the ones: they don't clean their boards when they leave a classroom; the desk is covered in their detritus like they just bailed on a bust; they'll send a pupil out of their lesson for 40 minutes rather than deal with the problem themselves; they walk into your room in the middle of a test because they "just need a few things". In a fair world you'd be allowed to fire a few BB gun pellets at them, just a couple of inches above their head, as a warning.
But life isn't fair. In many ways, working with multiple others in a close space is a contortionist's tango, like sex in a coffin. Their definition of cooperation might be your idea of insurgency. That's why, despite our own attachments and preferences, it's vital in a shared space to default to a safe common denominator of behaviour.
In other words, although you might think your kids' pictures on the staffroom fridge are a heartwarming treat for everyone, it's safer to assume that you're not the least biased judge of that. For my part, microwaving Cullen skink creates a smoked haddock aroma that transports me to the shores of Loch Fyne but I'm aware that this is probably not the consensus.
It's vital that when you share space with others, you don't steal it at the same time.
Schools are engines and they labour like the pump room of an ocean liner, not always efficiently or elegantly; all it takes is a few loose screws or a lost key and suddenly pistons strain to beat.
Every now and again, it's important to take the temperature of your own behaviour in the workplace - and why not at this time of year? Do you make it harder or easier for others to work around you? Are you sandpaper or hand cream?
It's an uncomfortable lens through which to peer. You can do it by reflecting on your day - by all means use a thinking hat if it makes you relax; just lock the door in case a grown-up sees you - or you can go one step further and ask a colleague. As long as it's instigated by you, in a conversation with someone you trust. I don't mean the self-imposed hell of 360 feedback so favoured by gormless consultants of yore, just a professional conversation. It's like asking your best mate if your breath smells.
How do you leave your classroom for others to find? How do you manage space in public spaces - staffroom, lockers and meetings? And what about that most wild of Wests, the school email? I long ago realised that promotion in any organisation depended as much on what you were seen to do as what you did - and boy, has email put gas in that tank. Sadly, the filter hasn't yet been designed to screen out the bloodless gags, the appeals for information that could be found in an instant of industry or the indiscriminate "send all" love letters (pressing "send all" should exclude you from voting in general elections, frankly).
Because if we're all going to work under the same roof, we're going to have to work in a way that maximises the needs of the many, not just the one.
Tom Bennett teaches at the Jo Richardson Community School in Essex and is director of the ResearchED conference