Higher continuing education can play a pivotal role in transmitting to professionals competences and skills for contributing to sustainable development. Therefore, this study aimed at (a) assessing the extent and depth of the content and practices related to sustainability in continuing education (CE) programmes and (b) encouraging CE programme managers (CEPMs) to reflect on how to promote a culture of sustainability through the content and design of a CE programme. Nineteen CEPMs evaluated 19 programmes from various sectors (information technology, health, social care, arts, business and economics, construction, etc.) of the University of Applied Sciences and Arts of Southern Switzerland using a checklist. The checklist reported four dimensions of sustainability—environmental, social, economic and cultural—and keywords related to them. For each keyword, the CEPMs were asked to indicate the relevance, extent and depth of transfer and describe practices related to the keywords. The results show a broad degree of application of sustainability-related topics, yet participants exhibited a tendency to deal with them rather superficially. The environmental dimension received less attention. The study shows the unfulfilled potential for promoting sustainability principles and highlights the need to train CEPMs and teachers.