Purpose: Higher education institutions (HEIs) have a pivotal role in global sustainable development. The purpose of this study is to assess the QualEnv Consortium's contributions (QualEnv, a cooperative network of 16 universities across several countries, aimed to promote sustainability within HEIs). This paper focuses on three key objectives: illustrating QualEnv's successful, replicable sustainability strategies, highlighting their application and outcomes and contributing to the discourse on sustainable practices in HEIs. Design/methodology/approach: This research uses qualitative and exploratory methods to provide an in-depth view of sustainability practices and strategies within universities. This study relies on documentation, specifically the "Sustainability Handbooks" of the QualEnv project, as a source of evidence. Findings: This study reveals that the QualEnv Consortium's strategies have significantly improved the environmental and social performance of participating HEIs. Notably, this research identifies substantial enhancements in key sustainability metrics, including reduced carbon emissions, increased adoption of eco-friendly practices and stronger community engagement. Research limitations/implications: This study has some limitations. First, the choice of a qualitative methodological approach may constrain the generalizability of the findings. Another relevant limitation is related to the uniformity in adopting sustainable practices. The effectiveness of actions linked to the Sustainable Development Goals may depend on consistency in implementation among participating universities, and variations in this aspect can affect the direct comparison of adopted strategies. Originality/value: This research contributes to the sustainability in higher education field by comprehensively examining the QualEnv Consortium's innovative approach. By focusing on QualEnv's experiences and outcomes, this research offers valuable insights and serves as a model for HEIs worldwide seeking to align their academic, research and community engagement efforts with sustainable development goals.