Peering up into the packed public gallery of Harrow LBC's town hall, Adam Lent recalls crowds of ‘furious' residents jeering and screaming. The year was 2002 and NLGN's new chief executive was a councillor at the London borough, which had just increased council tax by 20%.

The problem, Mr Lent says, was that the residents weren't involved in the discussions and didn't understand why the decision had to be made. The following year the council took a participatory budget approach in order to get those furious people around the table – and it worked.