When the question "What do you think the focus should be to deliver a sustainable London? was raised at Green Sky Thinking event, organised by Temple Group, early this year - the results were quite intriguing: Cycling infrastructure received 5.6%, green infrastructure received 22.2%, air quality received 27.8% and systems thinking received 44.4%. But what is Systems Thinking you might be asking? Nick Voulvoulis, a reader in Environmental Technology at Imperial College, who presented that morning provides useful insight.