This paper aims to understand how T-learning helps communities achieve better sustainability outcomes. On the basis of an intensive literature review and field research conducted in the Mekong Delta of Vietnam, the paper proposes a substantial linkage between T-learning and sustainability. It first outlines the environmental changes in Vietnam’s Mekong Delta, which appear to serve as “disorienting dilemmas” that force local people to learn and gradually shift their farming practices to align with a climate-resilient development. The paper relies on the outcomes of household surveys, field observations and focus group discussions to explore the impacts of T-learning on building adaptive capacity and sustainability transition in two community-based projects in Can Tho City and Ca Mau province in the Mekong Delta. Our findings reveal that T-learning enables experts and practitioners to introduce new ideas and accordingly mobilize local people to make changes without inciting doubt, dismay or concern. In an ideal T-learning approach, small-scale farmers learn from being under the supervision of experts in “field-based schools” that offer real-life experience and encourage learners to shift their livelihoods to eco-friendly agricultural practices. The paper sheds new light on how a critical approach to education for sustainable development through T-learning can be, under specific conditions, one strategy. It concludes that T-learning should be acknowledged as a potentially important part of the broader approach to climate-resilient development in vulnerable grassroots communities.