You may not have noticed from the headlines, but the G8 Summit was a real triumph for transparency. It was a brave and ambitious thing to put on the agenda, because it is not an easy issue to negotiate on. When it comes to the details, hundreds of different interests – many of them vested – put forward a series of complications. It is clear that there is still a lot of work to do on the transparency of businesses, particularly with regard to beneficial ownership.

But on the G8 governments’ own transparency, the summit didn’t get bogged down in the details. The leaders recognised that transparency has to cut across all aspects of government – and it will only really make a difference if all countries sign up to it. The Lough Erne Declaration could hardly be bigger picture: “Governments should publish information on laws, budgets, spending, national statistics, elections and government contracts in a way that is easy to use and re-use, so that citizens can hold them to account.”

By promising to deliver that, the G8 has got serious about putting its own house in order. Nor was this just a vague promise. The Declaration was accompanied by the Open Data Charter – an extraordinarily impressive document that commits G8 members to make all data open by default and sets out ways to improve its quality, quantity and – above all – its usability. The next step will be to show results before October, so that they can encourage other governments to join the Open Data revolution at the Open Government Partnership conference in London.

The narrative logic of making data available in order to facilitate accountability of governments to parliaments and people is compelling. But it can get complicated when dealing with the transparency of international flows. Here, again, though, the G8 has not shied away from making solid commitments about where their own money goes. The summit Communiqué reaffirms its members’ commitment to implement a Common Standard on Aid Transparency, made at the Busan High Level Forum on Aid Effectiveness in 2011, promising that “to show greater G8 leadership we will ensure data on G8 development assistance is open, timely, comprehensive and comparable.”

The phrasing is highly significant. Substitute “accessible” for “open” and you have Publish What You Fund’s four pillars of transparent aid. They are also the principles underpinning the International Aid Transparency Initiative (IATI). This matters, because there has been a degree of obfuscation since 2011 about what the Busan Standard involves. The Lough Erne Communiqué ends those arguments, confirming that it includes “both the Creditor Reporting System of the OECD Development Assistance Committee and IATI.”

That is a huge step. It means that all G8 members have now committed to IATI. As of last week, only four of them (the U.S., Canada, Germany and the UK) had done so. France, Japan, Italy and Russia joining the party deserves a lot more fanfare. It’s an historic step forward for aid transparency, meaning that the providers of over 90% of official development assistance are now signed up to IATI.

We at Publish What You Fund are happy to do our bit by offering our warmest congratulations to the French, Japanese, Italian and Russian governments. Welcome to the party! We’ll be raising a glass of champagne / sake / prosecco / vodka in your honour. We look forward to working with you and seeing your first publication to the IATI standard soon.

Once all G8 nations have fully implemented their promises, by the agreed 2015 deadline, it won’t just be possible for their own citizens to hold them to account. It will open the door for citizens in developing countries too. Open data is for everyone.