 Each year, around $150 billion flows from the richest countries to the poorest countries in foreign aid. So it's a fair question to ask, does foreign aid work? I've been working with UNUWIDER under the Recon Project for about 10 years, using new data and new methods to look at this question. Our main result is that aid on average does promote economic growth. If a country were to receive 10% of its national income in aid every year for 30 years, we would expect its long-run growth rate to be higher by about 1% point compared to what it otherwise would have been. But we need to be realistic. Most countries don't receive 10% of their national income in aid every year, so the impact is expected to be a lot smaller. And we need to be patient. The gains from aid accumulate over the long term, decades, not years. Good governance matters for development, for growth, for greater equality, for poverty reduction. And so the key question is, can aid support better governance? So the lesson here is that aid doesn't always support stronger states, but it doesn't always fail either. In order to better understand whether successful interventions can be replicated or adapted elsewhere, we need to think about local context. For example, should we expect a modern-day Marshall Plan to work for today's fragile states? Well, it's important to remember that Germany and Japan had historically strong state institutions before the war and during the war, and that's not the case for many of today's fragile states. Building states is different from rebuilding them.