GIRLS TALK IS a classic Dave Edmunds song, penned by Elvis Costello, and it captures in a few verses and choruses the complexities of a girl culture that thrives in the corridors and toilets of schools around the world. Movies like Heathers and Mean Girls helped bring the dark side of this secret society to mainstream attention and revealed it as a breeding ground for a stealthy kind of bullying that has long evaded notice and official consequence.

Few children schooled in the Western world escape experiencing or witnessing bullying, but what exactly is it? When we think of bullying we think of the traditional scenario: a bigger boy beating up a smaller boy or the infliction of a humiliating initiation rite on a terrified newcomer. We think of boys and we think of the body, or of persistent schoolyard name-calling. We know girls can bully, and most of us recall the “tough girls” of our childhood, but they were a rarity, seen as an aberration of girlhood.