A California study of the likely consequences of allowing schools license to modify substance abuse and violence prevention programs to meet everyday teaching needs suggests that it might not do much harm – most of the time.

The UK version of David Olds’s Nurse Family Partnership home visiting program, which epitomizes belief in the long term value and slowly accruing benefits of early intervention, is having to cope with familiar demands for short term payback to meet the anxieties of practitioners as well as politicians.

“Never doubt that a small group of thoughtful, committed citizens can change the world; indeed it is the only thing that ever has.” Public health specialist David Hemenway celebrates the achievements of the people who make baby walkers wider – and airplanes safer.