Indicator-based tools are widely used for the assessment of farm sustainability, but analysts still face methodological and conceptual issues, including data availability, the complexity of the concept of sustainability and the heterogeneity of agricultural systems. This study contributes to this debate through the illustration of a procedure for farm sustainability assessment focussed on the case study of the South Milan Agricultural Park, Italy. The application is based on a set of environmental, social and economic indicators retrieved from the literature review. The framework is based on three main steps: (i) Data collection mainly through interviews with farmers and institutions; (ii) data elaboration through an aggregative structure; and (iii) score analysis. The latter step includes a descriptive analysis that allows a comparison among farms or groups of farms and a principal components analysis that helps to confirm the dimensions in which indicators were previously included (components). Results derived from the sampled farms show that the framework can provide easy-to-read results useful at different levels. The study highlighted the procedures for the framework construction that is compatible with the region's context and objectives, using an analytical approach that aims at the use of balanced features of availability and reliability of data.