An increasing recognition of the impact of human activity on the natural environment has oriented attention to the role of education for sustainability (EfS) as a means to create more ecologically literate and sustainable societies. One premise is that socio-ecological sustainability issues and challenges are immediate and locally rooted. This calls for educational interventions that promote participative action by local communities, recognizing that adults in those communities need to engage in action and change towards sustainability. In relation to this, current evidence indicates that Information and Communication Technology (ICT) and the Internet have the potential not only to promote teaching and learning for EfS, but also to increase knowledge, and promote attitude and behaviour change of individuals and the broader community. In addition, sustainability issues are interrelated with other social dimensions with inherent complexity. Similarly, the design, implementation and use of ICT in education bring together learning and technology in complex ways. To address these types of educational contexts, both the ICT and EfS literature support a holistic and systems thinking approach. This suggests that developing a theoretical framework that informs the development of EfS websites, based on a systems thinking approach, might be an effective way to enhance ecological literacy, and action competence for socio-ecological sustainability at the community level. Within this context, this PhD research study aimed to investigate the use of Internet websites for community EfS in Chile. A theoretical model for the design and development of EfS websites aimed at the community and non-formal level was developed based on literature from EfS, systems thinking, ICT, and community education. This model was trialled in an authentic context in Chile, through the design and build of an EfS website addressing the ecological sustainability issues of a lake, and its impact on the local community and visitors. Key considerations of this model relate to a deep understanding of the local, social and cultural characteristics and needs of the target community, and associated sustainability issues; the use of culturally meaningful ICT affordances such as multimedia, Web 2.0, and social networking tools; and the inclusion of EfS pedagogical considerations and strategies for learning, such as promoting ecological literacy, critical thinking and action competence through knowledge integration and challenging beliefs. Within a naturalistic paradigm, using an interpretive methodology, and following an activity theory analytical framework, the evaluation of the use of the EfS website by 24 local participants was conducted through the following research design. Firslty participants were administered a pre-intervention questionnaire, which assessed participants’ prior knowledge related to ICT use, and to local sustainability issues. Immediately after they were invited to visit and browse the EfS website for a period ranging between 10 to 20 minutes. Following participants’ use of the EfS website, a post-intervention interview explored participants’ perceptions, understanding change, and motivations to take action. Finally, a follow-up online survey assessed participants’ change in understanding, actions, and adoption of sustainable living principles, based on revisits to the EfS website during a period of five weeks, five months after their first visit. Findings indicate that EfS websites are culturally shaped tools with the potential for facilitating transformative understanding processes, and empowering community members in engaging in action and participation towards socio-ecological sustainability at the local community level. A key aspect of the successful use of EfS websites for community education is to achieve meaningfulness and relevance through the website on local community members. Different considerations from the theoretical model appeared to have contributed in to the achievement of such relevance in the Chilean community addressed in this study. These are fully presented and explored in the coming chapters. The expected contribution of this study is to inform the literature on the effective use of ICT to enhance practice of EfS at the community level.