Who owns the troubled families agenda? Is it the DCLG, the Department for Work and Pensions (DWP), the Department for Education, the Cabinet Office, or all of them together – or none?

We all know the communities secretary Eric Pickles won that particular turf war when he managed to persuade his colleagues, late last autumn, to place the Troubled Families Unit under 'Broken Britain' tsar Louise Casey within the DCLG, on the grounds that it was a local government issue.