Designers have recently become increasingly involved with small-scale producer communities around the world, mostly in the southern hemisphere, and this increase has highlighted the significance of these encounters in the creation of economic and social opportunities for those peoples. This study identifies that, however, these encounters present challenges and imply ethical responsibilities that current design methodologies fail to embrace in their long-term goals. This research investigates the interaction between designers visiting local producers whose livelihood is deeply dependent not just on the natural environment and their local culture but also on the process of fabrication. This thesis proposes a new methodology to guide designers and producers through a reflective process of social change in producer communities. This methodology derives from a combination of activity theory and the capability approach to wellbeing applied within design and producer community practices. The aim is to support a dialogical and holistic design approach to this kind of cooperation, as well as to endorse research and professional practice in the field of design for social change. This research seeks to break new ground by generating perspectives that support both designers and local producers in tackling and resolving issues of individual and collective wellbeing. The research draws on interviews with designers working with local producers in different countries. In addition, the author presents her own experiences of researching and working with Amazon rainforest rubber-tapping communities which have adopted new production methods in order to acquire new capabilities and help conserve their environment. Two case studies illustrate the reflective methodology applied to the designer and producer interactions within social innovation and entrepreneurship. But it is fundamentally the materiality of the rubber, and the revelation of the interdependences within and without the locality, that form the framework of this thesis.