None of it is new, of course. Youth and excess go together and “substance” problems of one kind and another thread their way through history. Wormwood, peyote, tobacco, gin, amphetamine… take your pick. But for Blueprints conference delegates the modern danger is inescapable: it’s time to worry about the damage drink, drugs and both together are doing to young people the world over.

Randomly allocating children to care in order to test its effectiveness continues to be a contentious proposition, particularly in the US; Oregon researchers have been able to remedy the scarcity of impact evidence by using randomized methods to test the value of giving foster parents expert support.

Initiatives from the universities of Washington and Georgia, both focusing on efforts to intercept the dangers of alcohol abuse before they trigger other problems at home or at college, are getting good early results.