I decided to give up flying for work and leisure in 2000 on the ground that it was destructive and avoidable, and have flown just twice since – once for work and once for family reasons. I intend to avoid flying if at all possible. It restricts one’s academic career, but ask yourself how many conferences really make any difference. Can one’s example shift the culture? Not on its own; but in concert with a network of like-minded others, yes.