Why are students who have special educational needs at greater risk of bullying than their peers when educated in mainstream settings? This case study of one mainstream secondary school describes the various facets of the peer group dynamics that underpinned social aggression and exclusion towards students who were hearing impaired. These students were subject to the same social pressures as their mainstream peers but in addition were at risk of stigmatisation. As a result of their deafness they were treated as second class citizens (discredited). This in turn could lead to denigration and actual bullying, as well as social exclusion/marginalisation. (Contains 1 figure and 4 notes.)