Next week sees London out in force for Climate Action Week. Z/Yen and Long Finance will be talking about sustainable finance centres, building on our development of the Global Green Finance Index (GGFI). The index, first published in March 2018, tracks the progress of financial centres in terms of the intensity or depth of green finance in the centre; and the quality of the green finance taking place.

London has been at the top of the quality ratings since the first edition of the index; and Western Europe generally performs well. Climate Action Week is one example of how London is taking a leading role in green finance.

The results of the GGFI overall demonstrate that cities that take a leadership role perform well in the index. People are more likely to bring their business to a city that is showing leadership – to trust that there is substance behind the institutions that are active in developing and delivering green finance – and that there is profitable business to be done.

Part of leadership is sharing ideas and collaborating with others. In a competitive environment, this may seem an unusual approach. But the reality is that in green finance as in other areas, the more you work with others, the better links develop between people in different parts of the world. Collaboration and sharing knowledge is key to maximising business opportunities.

Events such as Climate Action Week help to ensure that London will learn from others. No city or country has all the answers to the challenges that face us in building financial systems which contribute to the sustainable economy of the future. It is through sharing expertise and approaches that have worked in one place that they can be applied elsewhere.

One way we are working with this grain for the GGFI is to develop and publish case studies on the centres which take a lead in different regions of the world in green finance. We published most recently a case study on São Paulo, Brazil. The intention of these studies is to share knowledge about how leading centres have taken that lead – whether through government action and regulation, disclosure incentives, leadership from financial institutions, or a combination of these.

The sharing of ideas through collaboration and sharing has the potential to lead to change. Just as a nuclear chain reaction leads to enormous releases of energy, so a chain reaction of ideas – one idea sparking another, which influences the approach taken by five people, then fifty – can lead to enormous shifts in greening the financial system.