Based on a close collaboration with industry partners and the implementation of collaborative online international learning (COIL), this research explores a learning approach aimed at enhancing sustainability awareness within an English for Specific Purposes (ESP) course, offered to Portuguese students. Thus, students were challenged to enroll in an online international micro-credential, i.e., “Education for Sustainable Development”. This micro-credential was structured to encourage students to identify and systematize relevant information pertaining to sustainability in the industry, to increase the students’ awareness of the importance of implementing sustainability actions within various industries and to prepare well-structured information, demonstrating rigor in the use of sustainability-related terminology. The outcomes included multimodal communication elements and supplementary materials, encouraging students to engage with sustainability issues comprehensively and practically. In this study, the authors present preliminary research findings, based on the students’ answers to a questionnaire, focusing on the project’s strengths and weaknesses, as well as on the competences they have developed during the project. Although some weaknesses were identified, by integrating sustainability awareness into ESP learning, the project not only enhanced students’ ESP proficiency and communication competences, but also cultivated a deeper understanding of sustainability challenges and solutions within industry settings. Additionally, working in international teams fostered the development of their international collaboration and digital competences.