Purpose: This paper aims to determine, from key actors' perspective, how sustainability has been integrated into the policies and strategies of higher education institutions (HEIs), particularly Portuguese public universities, within the framework of the United Nations Decade of Education for Sustainable Development (UN DESD) 2005-2014. Design/methodology/approach: Semi-structured exploratory interviews were conducted after gathering a sample of 15 key actors in decision-making processes who designed and implemented Portuguese education for sustainable development (ESD). Seven interviews with the key actors were undertaken and analyzed, leading to other plans, policies and programs that were not publicly accessible. Findings: The main findings are the lack of commitment from governmental institutions to implementing ESD at the university level and how few documents are partially linked to sustainable development, according to the key actors' opinions. Nevertheless, Portuguese universities' autonomy and their social responsibility have lead them to develop several initiatives and policies toward ESD. Research limitations/implications: Convenience sample does not allow results to be generalized to all Portuguese HEIs. Future investigation will be undertaken, including the analysis of plans, policies and strategies at university level, and a questionnaire survey will be applied to those responsible for implementing sustainability in Portuguese universities. Practical implications: This study provides findings, conclusions and recommendations that ultimately motivate HEIs to achieve sustainable development and to be more effective in integrating sustainability into their policies and strategies. Originality/value: The paper contributes to the literature by reflecting the lack of integration of policies and strategies in HEIs in a southern European country (Portugal), within the framework and goals of the UN DESD 2005-2014, and by explaining similar patterns probably existing in other countries.