Never waste a good crisis: so President Obama's former adviser, Rahm Emanuel, was supposed to have said in the middle of a tough part of Obama's first presidential campaign. It's advice that both David Cameron, on the issue of Europe, and Ed Milband, on unions, have been given repeatedly in recent weeks.
However, what is good advice for politicians can feel challenging for charities, as I found out when I got on the wrong side of Alastair Campbell and the No 10 media machine in the pages of a national newspaper. When a charity is embroiled in a crisis, it is essential to have a supportive board and chief executive, as well as a clear message to communicate.
Yet a crisis can bring clarity and the opportunity to define what you stand for. It can give you the opportunity to ditch old positions, move public awareness towards your issue and create a better understanding of your organisation. Of course, it depends on the crisis, but assuming that you've not done anything perfidious, you should view every threat as an opportunity. Conflict creates interest, which is crucial to communication. Some basic rules are helpful, as follows.
* It is essential to ensure that you are able to define what the conflict is about, rather than allow the discussion to be defined by events or by those who are attacking you. Use the opportunity to define what it is that you stand for, and challenge those who attack you to articulate why this is wrong.
* A crisis can also be a great opportunity to restate your positions and bust any myths that your opponent is trying to lay at your door. If you need to change something that your organisation is doing, make this change quickly and explain why. Present the change as a positive - for example, by showing how you have listened to criticism and changed.
* You should see critics as potential future allies and try to win them over, not beat them into reluctant submission. Look for points of agreement and build on those.
* If you are responding to external events, there needs to be sensitivity and good judgment, so you are not perceived to be cynically trying to exploit an issue or intrude on personal grief. Crucially, you should not invent a crisis where there is not one. Cheap publicity will only devalue your organisation's currency, because the public and supporters will rightly judge you harshly for crying wolf.
Restating the case
We have seen some good examples of internal or external crises giving charities opportunities to communicate and define the issues. Recent attacks by think tanks on campaigning charities - claiming that they were simply part of government-promoted lobbying - were potentially damaging. But this gave charities the chance to restate the case for campaigning, while also exposing some of the myths being promoted.
Last year's government U-turn on charity tax relief - when proposals laid out in the Budget to cap relief on certain charitable donations were scrapped after a campaign of opposition - gave the sector a platform to explain how it used philanthropists' money and get the change overturned. As a consequence of this, public understanding of charity finance improved.
So don't fear a crisis - whether internal or external - but use it instead to define who you are, what you represent and why we should care.
Brian Lamb is a consultant and chair of the NCVO's campaign effectiveness advisory board