Ecovillages, Timebanks and a Local Exchange Trading Schemes are part of global social movements as well as offering innovative approaches to local sustainability. The current study looks at these three community-economic initiatives as a means of addressing the connected social, economic and environmental challenges of local sustainable development. Investigating these collective practices builds on current approaches to studying pro-environmental behaviour change in the social sciences. Two research questions structured this investigation. These focussed on i) how members understand their experiences within the selected groups and ii) processes leading to the formation, maintenance and contraction of the initiatives. Five individuals were interviewed from each group and interviews were analysed using Interpretive Phenomenological Analysis. Secondary data sources also contributed to a broad analysis of group processes and contexts. Diverging from traditional approaches, this multi-level, interdisciplinary account is able to capture more of the complex reality of these organisations than would be possible within a single discipline or through focussing on a single element of group membership. Indeed this comprehensive approach to studying community-based models for sustainability is the unique contribution of this study, moving forward methodological debates in this field. Findings that emerged from this study emphasise group members’ motivation to enhance their personal resilience. Participation provided members with a sense of agency and community connection, as well as being a means to express alternative cultural identities. Informal reciprocal exchange was also preferred to more formal exchange practices, with implications for the understanding and development of community exchange systems. This study widens the focus of environmental psychology to include socio-economic practices, and contributes towards the growing interdisciplinary field of complementary currencies and grassroots innovation. Finally, it provides a template for the evaluation of sustainable community-economic initiatives more generally. The thesis concludes that these initiatives and their wider movements are a promising avenue for research and development in sustainability.