I’d like to propose a new standard for school leadership. I’ve had a look in the Department for Education’s published standards for headship and, although there’s some good stuff in there, I can’t see this vital attribute.

I’d like to title this new professional standard “Ignoring Things and Saying No”. We need more of this, even though I know it runs counter to many inspirational guides to leadership, which say leaders are expected to be deeply in tune with the outside world and relentless in their ambition.

All good standards come with levels or grades of increasing sophistication. My new standard has them too:

• Level 1: tactical procrastination - at this level, the leader wisely knows that if they wait long enough, the initiative will be cancelled and another priority will take its place.
• Level 2: lip service - at this level the leader is good at looking like they’re ticking all the boxes but continues to pursue their own vision beneath the surface compliance. 
• Level 3: shameless hijacking - at this highest level of maverick excellence the leader actively uses external forces to pursue their own ends. They leap on initiatives they were going to do anyway in order to obtain additional resources and funding; they rebadge their long-held goals using the catchphrase du jour.

You may detect a note of flippancy here, and you wouldn’t be wrong. But I have a serious point. Of course it is a leader’s job to be aware of what’s going on externally and to think of the future; not every new policy is bad. But that doesn’t mean you have to then import every zany idea going or over-comply with every government announcement. Part of being a great leader is having your own vision and a set of priorities about what your school and community need. Sometimes you have no choice but to comply - it’s the law - but other times there is more flexibility than we might expect.

Part of a leader’s job is to hold an umbrella over their school, to shelter it from the buffets of the outside world. Perhaps a filter would be a better analogy but it is less catchy. You select what comes in and what doesn’t: “This is good, let’s leap on it”; “This is compulsory but irrelevant, let’s do the bare minimum”; “This is harmful, let’s ignore it.”

This can go too far. It is not a leader’s job to protect their staff at the expense of the students or to create an easy life; that’s not what I am talking about. You absolutely do hold people accountable but you look at the evidence and you do it in your way, to your priorities and in tune with your values. You are not a mere conduit for someone else’s accountability. In a system where a lot is wrong you can still build a school where a lot is done right. The price is accepting some level of personal risk.

Strategy is the art of sacrifice. In a world of limited resources, it is about what you choose not to do as much as what you choose to do. This can be painful. There are so many good things you could do; it is rarely a choice between good and bad but between good and better. And you may not even have strong evidence for which is which. A few things done well and sustained over time may well be more effective than many things done averagely for a bit and then dropped for the next big thing.

Leaders, this matters for your own health and career longevity too. School leadership is an unfinished and unfinishable job. If you refuse to go home before you’ve done everything you could do, addressed every potential problem and ticked every box, you will never go home. If you work yourself into exhaustion pursuing every possibility, you will lose perspective and make mistakes. You will probably exhaust everyone around you too. There must come a cut-off point. You do the most important things right up to the limit of your sustainable capacity and then you stop. And do something completely different with your family, friends, nine iron, Downton Abbey or other loved ones. This, of course, means knowing what’s important. But that’s a leadership standard that I hope we all agree on.

People will argue that the government’s chaotic, overloaded and punitive reform programme makes this harder. They will argue, as I have, that the level of leadership risk is too high. This is right and we must make these points but leaders will always face these choices, whatever the external climate, and they matter even more when it is so inclement.

Russell Hobby is general secretary of the NAHT heads’ union

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