Natural pozzolanas are very reactive with calcium oxide (CaO) provided by lime, the effectiveness of the stabilisation mainly depending on the amount of low alkali alluminosilicate glass phase. Nevertheless there is a lack of systematic studies on the suitability of pyroclastic soils to lime stabilisation, and the effects of the treatment parameters on the engineering properties of the stabilised material. In this paper the preliminary results of experimental research on lime stabilisation of pyroclastic soils are presented. Two pyroclastic soils have been considered in this study. The first is a sand with gravel belonging to a pyroclastic flow deposit of the Colli Albani volcanic complex, and the second is a silty sand originated by the late activity of the Somma-Vesuvius. The results on natural and lime stabilised samples allow a first overview on the suitability and the effectiveness of lime stabilisation of pyroclastic soils. © 2011 Taylor & Francis Group, London.