Southern Connecticut State University research drawing on in-depth focus group conversations conducted between August and September 2013 and July and August 2015. Eight focus groups comprising of 42 participants were conducted in 7 communities in the UK: Blacon in Chester; Congleton in Cheshire; Northwood in Stoke-on-Trent; Sefton in Liverpool; Chorlton in Manchester; Govan in Glasgow; and Meersbrook in Sheffield. These communities were chosen because they either incorporated examples of sustainable lifestyles, or because of a record of environmental policy combating fuel poverty and establishing energy conservation projects. The findings from this paper outline that within communities, individuals clearly demarcate between “us” and “them” with reference to other people’s participation or non-participation with community-based sustainability. Those that do not share the same attitudes, are viewed as either more or less radical, or do not contribute in similar ways are marginalised and “othered”. These considerations have the potential to project particular barriers on wider community engagement if left to develop, cause tension, and are not resolved.