SUMMARY
Aim of the paper is to present the results of a research experience focused on the setting of a sustainability indicator in presence of risk/uncertainty over time. Firstly, a literature review of the most widespread methodologies for the evaluation of project economic sustainability in a life cycle perspective is presented, extrapolating the most relevant research lines; secondly, a four steps research experience is illustrated. The methodology for calculating a stochastic economic-environmental indicator is proposed, by adopting a stochastic Global Cost approach to solve Life Cycle Cost Analysis (LCCA). The input for the analysis are modeled through Probability Distribution Functions, while the durability of components is modeled through the stochastic approach to the Factor Method.