Environmental education can play a major role in achieving sustainability. In the context of this research, environmental education is defined as a process to impart and instil knowledge, skills, attitudes, motivations and commitment among the population to work towards environmental solutions, problem prevention and to live sustainably. This research focussed on non-formal environmental education with adults in communities in Sabah, Malaysia. In Sabah, solid waste is a significant problem, and oil palm plantations are one of the main agricultural activities that produce solid agricultural waste or by-products in rural areas. This research focussed on co-constructing an environmental education programme for waste management with villagers, including the independent oil palm smallholders, in local communities in Beaufort, Sabah. This research has elements of both interpretivism and a critical theory approach. It has elements of interpretivism because of the interaction with the local communities to obtain their views and perceptions on waste management practices in their own areas. It was also partially aligned with the critical theory paradigm because it sought to create positive changes among the communities in terms of waste management practices by providing an avenue for discussions, creating empowerment and collaboration. The theoretical principles of community environmental education drawn from the areas of community education and environmental education guided the framing of the research design. Data were collected in two stages. Stage one involved interviews with government officers, a community survey and a focus workshop with two rural communities. This data combined with the theoretical principles of community environmental education guided a co-construction of an educational programme on waste management for the two communities. Stage two involved the programme implementation, and an evaluation process which included a survey, interviews and observation. All closed and scale questions in both surveys were analysed quantitatively. The open-ended data gathered from the questionnaires, interviews, focus workshop and observation were analysed using thematic analysis. This study found that the communities had a genuine concern for the environment and a desire to improve their waste management practices. However, they did not seem to know how to do so, and their knowledge of environmental and waste management issues seemed low. An attitude-behaviour gap in which favourable environmental attitudes were not matched by environmentally-friendly behaviours was also observed. The community members were unaware or uncertain about guidelines that might guide their waste management. It was also reported there was a lack of environmentally-friendly options such as waste disposal and recovery facilities and services, as well as alternatives for proper disposal in their villages. Change in attitudes and behaviour among the community seemed slow to progress, and it was found that changes in waste management practices at a personal level were easier to effect, rather than as a community. The findings of this research indicated a tendency towards pro-environmental behaviour motivated by goals other than environmental; in this case, monetary gains or incentives. The evidence in this research showed that it was possible to co-construct an environmental education programme with local communities. The programme was co-constructed and implemented based on the literature and data on the perceptions, needs and current situation of community waste management through the perspectives of the government officers and local communities. There was clear evidence that the programme made a difference in a short-term; however, long-term outcomes of the programme were not apparent. This study has shown that a model developed from theoretical principles of community environmental education provided useful guidance in practice but that implementation of the model in local contexts has many constraints that need to be considered.