Despite an increased focus on education for sustainable development (ESD), many teachers still report insecurity in how to implement ESD in their practice. This study examined teachers’ reflections from using the local environment as a learning arena in ESD (6th-9th grade). Results from analysis of semi-structured interviews showed that the teachers experience challenges with the complexity of sustainable development, the ambiguities in the curriculum and time spent if the learning arena is some distance from school. However, the teachers strongly argue for using the local environment as a learning arena in ESD, and their arguments were mainly within four categories: 1) exemplification of various perspectives of sustainable development, 2) authentic and concrete learning, 3) opportunity for action, and 4) affective influences. The results from this study, emphasizing the teachers’ perspective, can contribute to a shift in focus from abstract education policy on what ESD should be, to a focus on contextualized practice.