Resumen: This paper contributes to the literature about sustainability assessment and goes a step further by studying the effect on university performance. The aim is to analyze, from an external perspective, the relationships between the three dimensions of sustainability in universities (environmental, economic, and social), the similarities between universities, and the impact that it can have on performance. In order to carry out an empirical assessment for Spanish public universities, an index is proposed to measure sustainability through indicators for the three dimensions. The results show that there is a positive correlation among the three dimensions, but only the association between the environmental and the economic dimension is statistically significant, which evidences that there is not an integrated perspective of sustainability. Although there are no common patterns among universities, some similarities among them were found. Finally, the paper shows that the entities that integrate sustainability in their plans and activities have a positive impact on performance. Idioma: Inglés DOI: 10.3390/su11195302 Año: 2019 Publicado en: Sustainability (Switzerland) 11, 19 (2019), 5302 [21 pp.] ISSN: 2071-1050 Factor impacto JCR: 2.576 (2019) Categ. JCR: ENVIRONMENTAL SCIENCES rank: 120 / 265 = 0.453 (2019) - Q2 - T2 Categ. JCR: ENVIRONMENTAL STUDIES rank: 53 / 123 = 0.431 (2019) - Q2 - T2 Categ. JCR: GREEN & SUSTAINABLE SCIENCE & TECHNOLOGY rank: 26 / 41 = 0.634 (2019) - Q3 - T2 Categ. JCR: GREEN & SUSTAINABLE SCIENCE & TECHNOLOGY rank: 6 / 8 = 0.75 (2019) - Q3 - T3 Factor impacto SCIMAGO: 0.581 - Energy Engineering and Power Technology (Q2) - Environmental Science (miscellaneous) (Q2) - Renewable Energy, Sustainability and the Environment (Q2) - Management, Monitoring, Policy and Law (Q2) - Geography, Planning and Development (Q2)