If you mention impact measurement to those in the sector, the response is often a tight smile or even a wince: as Nick Hurd, the Minister for Civil Society, said last week, many people hate it. At the same time, they realise they can't dodge it because it's here to stay.
Strong evidence for this came in the recent study by Professor Fergus Lyon and Dr Malin Arvidson for the Third Sector Research Centre. Thirty-two of the 40 organisations they interviewed had used impact measurement, often to "satisfy powerful players in a market place for contracts and philanthropy".
They also reported that there was "much discretion" in the way impact measurement was used, that funders were seen as using it as a means of control, and that some organisations working in a competitive market place feared that rivals were inflating their results.
This is why Hurd was quite right to say that it's the government's job to simplify things by producing common metrics from what he called "the profusion of methodologies". Cabinet Office officials are on the case, and one of them told a Third Sector conference recently it was going to take several years to get it right.
Meanwhile, New Philanthropy Capital, the harbinger of impact measurement in recent years, plans to continue and refine its work, as its new chief executive Dan Corry says on page 10.
It won't be hard to create standard measurements for, say, child vaccinations or citizens transported to hospital appointments. It will be much more difficult to create them for services that help - tired but necessary phrase - some of the most vulnerable in society. How do you fairly measure distance travelled in a journey that is never going to end with a neat tick in a box marked 'employed' or 'cured' or 'back on the rails'?
That's the real challenge for impact measurement - to make sure that the legitimate calls for better figures do not, in a payment-by-results culture, divert resources from activities that make for a charitable and compassionate society.