From Baroness Valerie Amos et al.

Sir, Global corruption in all its forms, from looting state budgets to laundering money, is one of the most unjust, corrosive and dangerous issues of our time.

Corruption is a punitive tax on business, inhibiting job creation and prosperity. It fuels support for extremism and facilitates terrorist financing, making our world a more dangerous place. It erodes trust in our police, our courts and our politicians, making our world less just and fair. It doesn't just hinder economies — it prevents people from reaching their true potential.

Corruption diverts precious government resources away from schools, hospitals and other essential services, and locks people into poverty. An estimated $1tn is siphoned out of developing countries each year through money laundering and dodgy deals — money that could generate tax revenues to invest in fighting poverty, stimulating growth and creating jobs.

We urge delegates of the Anti-Corruption Summit in London on May 12 to agree to these eight steps:

1. The public should know who owns and profits from companies, trusts and other legal entities.

2. We need tighter rules to stop corrupt money being spent on property and luxury goods.

3. Banks and businesses should be required to find out who they're dealing with, and report it if they come across shell companies or dodgy practices.

4. Companies buying oil, gas and minerals, and those in the defence and construction sectors must make details of their payments to any government, on any project, available to the public.

5. Companies should reveal how much tax they pay in every country they do business in.

6. All government contracting processes around the world should be open.

7. All government budgets around the world should be available for anyone to view.

8. Corruption hunters should have access to timely, comparable and relevant open data on the issues above as well as the technology that will allow them to work effectively.

Taken together, these steps will help create a new international norm — a Fair Play Standard — which will focus our efforts to stamp out corruption. Looking the other way is no longer an option. We must act together with courage, ambition and urgency to put an end to this scourge and make our world a fairer place.

Baroness Valerie Amos
Paul Polman
CEO, Unilever
George Soros
Chairman, Open Society Foundations
Bob Collymore
CEO, Safaricom
Mo Ibrahim
Mo Ibrahim Foundation
Winnie Byanyima
Executive Director, Oxfam
Sir Paul Collier
Oxford University
Bono
José Ugaz
Chair, Transparency International
Dominic McVey
Entrepreneur
John Githongo
Anti-Corruption Campaigner
Guilherme Leal
Co-Founder, Natura Cosméticos
Bob Geldof
Eloise Todd
Global Policy Director, ONE Campaign
Rakesh Rajani
Ford Foundation
Gillian Caldwell
CEO, Global Witness
Martin Tisne
Omidyar Network
Caroline Kende-Robb
Executive Director, Africa Progress Panel
Sarah Chayes
Author, Thieves of State
David Peter
ICE BT