The concentration of industrial activities located close to residential areas poses problems of land use planning, risk control, emergency planning and responses to public authorities. The decision-making process requires the analysis of a large amount of information on risk sources, accident modelling, population distribution, etc. The treatment of such information needs the support of informatic tools. ARIPAR version 3.0 is a software package that implements a probabilistic methodology for the assessment of the risks of complex industrial areas, including transport of dangerous substances, to obtain a number of different risk measures. The paper illustrates the basis of the methodology and the main features of the software; some elements from real applications on industrial areas in Italy are presented as well.