Can nudging promote sustainable consumption behaviour? This study investigates if nudging promotes more environmentally-friendly purchases when applying either a default option or adding a product to elicit the attraction effect in a consumption situation of electronic products. The study further investigates sustainable consumption behaviour by looking at political orientation and the degree of climate change denial. The results show that nudging can promote significantly more environmentally-friendly purchases. The attraction effect was found to have positive effects, but not the default option. A higher proportion of environmentally-friendly purchases was further carried out by participants having a lower denial towards climate change. Climate change denial was also correlated with political orientation; participants evaluating themselves as right-wing oriented showed higher climate change denial, and proceeded with less sustainable purchases. Despite identifying positive effects of nudging on sustainable consumption behaviour, data also indicate an interaction effect between nudging and the sequenced presentation order of condition. This can be interpreted as a carry-over effect moderating the effect of nudging when it is presented after a control condition. This moderating effect is discussed as a potential limitation of nudging as a tool to affect people’s behaviour.

The urgency for a drastic reduction in greenhouse gas emission is emphasised in the new Special Report on Global Warming of 1.5 °C by Intergovernmental Panel on Climate Change, in order to maintain the security and sustainable development of humanity. As proposed in the report, changing individual consumption behaviour can considerably alleviate the environmental impact of consumption and emissions. However, transforming individual to sustainable consumption behaviour has proven over time to be a challenging task involving all aspects of the society and industry. Sharing practice is a form of collaborative consumption proven to be applicable in fulfilling user needs with minimised environmental impact and material consumption as well as creating a sustainable consumption behaviour. A case study is conducted on the online peer-to-peer stuff sharing platform to discover what challenges users to perform sharing practice, what influences the participation in sharing practice, and what strategy a platform can have to stimulate the participation in sharing practice. The method of this thesis is a qualitative content analysis of the user reviews from the online stuff sharing platform, and the approach is inspired by grounded theory. The findings of the thesis present the difficulties of platform users in sharing practice, i.e. information transparency, arrangement, quality, security, and user knowledge. Also, the findings state the factors underlying identified difficulties, namely social presence, competence in sharing practice, and platform responsibility. The study concludes with strategies that can be applied for optimising sharing practice and platform. Besides, the initiative of the platform is highlighted to create transformation toward sustainable consumption behaviour. Otherwise, the development of sharing practice can be jeopardised. Besides, further research is necessary to establish a holistic outlook of sharing practice and facilitating the transformation toward sustainable consumption.