This paper presents a framework for analysing the degree of consideration of sustainability principles in Strategic environmental assessment (SEA), and demonstrates its application to a sample of SEA of Italian urban plans. The framework is based on Gibson's (2006) sustainability principles, which are linked to a number of guidance criteria and eventually to review questions, resulting from an extensive literature review. A total of 71 questions are included in the framework, which gives particular emphasis to key concepts, such as intragenerational and intergenerational equity. The framework was applied to review the Environmental Report of the urban plans of 15 major Italian cities. The results of this review show that, even if sustainability is commonly considered as a pivotal concept, there is still work to be done in order to effectively integrate sustainability principles into SEA. In particular, most of the attention is given to mitigation and compensation measures, rather than to actual attempts to propose more sustainable planning decisions in the first place. Concerning the proposed framework of analysis, further research is required to clarify equity concerns and particularly to identify suitable indicators for operationalizing the concepts of intra/inter-generational equity in decision-making.