We have studied the pressure induced B1-B2 transition and the elastic behav
iour of KBr using three-body potential model. It is found that the inclusio
n of the three-body forces in the potential model yields more reasonable va
lues of phase transition pressure, second-order elastic constants and bulk
modulus than those obtained by others (wherever available). Results of high
-pressure experiments carried out on KBr for volume transitions are also re
ported in this paper in order to verify theoretical studies.