Aid doesn't always work.

Is that what you expected the chief exec of an NGO serving more than 50 countries to say? No? I'm not surprised.

The quality of the debate around UK government spending on aid has been pretty dire. We've allowed ourselves to become polarised, so the development sector say 'aid is good' whenever we're asked about the government's commitment to allocate 0.7% of the country's income to overseas aid. And the naysayers say aid is rubbish.

And nothing much is achieved, really, except for screaming headlines that make people angry for the wrong reasons.

Because, of course, we should be angry.

We should be angry that, even though there is enough food in the world for everyone, one in seven people will go to bed hungry tonight. We should be angry that this is the case in the 21st Century, even though we've made massive advances in so many other areas of life. We should be angry that we've allowed ourselves only to be persuaded by very simplistic representations of poverty and need, and haven't got the time or the energy to think about the complexities of the trade system, land ownership, climate change, or abuses of power that combine to perpetuate the injustice of hunger.

Those of us working in the development sector know that it's complex. We carry out research, write comprehensive reports and test various methodologies to find out how to address the complexities. Every day, we talk to governments about how their aid could be more effective, and we review our own programmes too. We all, both NGOs and government departments, work extremely hard to resource, train and inspire people living in poor communities to find their own ways out of poverty.

And, much of the time, it works. We've come a long way in recent years, thanks mostly to the widespread agreement that extreme poverty should - must - become a thing of the past. We've found lots of ways to improve the health of children, to make education available in communities that have never had it before, to make sure people have clean water and a safe place to go to the loo.

For example, the proportion of people living on less than $1.25 a day fell from 47% in 1990 to 24% in 2008. That's happened within our own lifetimes, and represents a huge amount of progress.

But occasionally aid doesn't work in the way that it should, or aid isn't enough to get the heart of the problem. And those are the times we need to pay lots of attention; not so that we can beat ourselves up, but so that we can learn why it didn't work and so do it better next time.

Scrutiny is good. We should do it more. We should do it better. We should do it all the time, so we can be very clear about how our money - especially our taxes - is being spent. The Department for International Development is already one of the most scrutinised departments, with an Independent Commission for Aid Impact and an International Development Select Committee, on top of the National Audit Office which looks at all aspects of government spending.

Scrutiny, when done well, puts the focus on experimentation, feedback and rapid real-time learning. We learn to adapt by making small changes, observing the results, and then adjusting. This is the exact opposite of the planning approach, widely used in development, which involves designing complicated programmes and then tracking milestones as they are implemented.

That scrutiny will work best when we do it openly. We should be having conversations on Question Time about the comparative merits of microfinance, social entrepreneurship and grassroots advocacy.

We do it with other areas of government spending. We rightly have open scrutiny processes, through local authorities and inspection bodies, of NHS trusts, police forces and schools. These are made public and they attract a lot of attention, which is sometimes painful but is always focused on making services better.

So why isn't the conversation about international aid framed in this way?

Because, as long as we're arguing about whether aid is good or not, we're missing the point. There are billions of people who are not having their most basic needs met, and we have the power to change that; especially if all the other rich countries join with us in allocating 0.7% to overseas aid.

If we were talking about this stuff, we'd be shouting about the hidden gems of development, like the thousands of local churches in poor communities which are seeing incredible results because they're made up of local people taking their own decisions instead of having things done to or for them.

So surely, the real question isn't whether to spend government money on aid; it's about what's working and what isn't, so we can get behind the things that are working and so become much less reliant on aid in the future? And it should also be about what else the government could do, as well as giving aid, which gets to the heart of tackling some of the complex root causes of poverty.

That would be a great debate to have. It wouldn't be simple, because life isn't straightforward and the causes of poverty are extremely complex.

But it would be more honest, more useful and more dignifying to the people we're serving than the vitriol we're seeing in the news at the moment.