It is well known that heterogeneous chemistry plays a very important role in global ozone dynamics. A survey of new observations and numerical modelling results has been made to analyse the potential impact of volcanic eruptions on the stratospheric ozone layer in the context of the heterogeneous chemical reactions on surfaces of volcanically produced stratospheric aerosol particles. An important aspect of the problem is that volcanically induced ozone changes may lead to a substantial impact on the radiative forcing for the surface-troposphere system and, subsequently, on climate.