Purpose – The purpose of this paper is to gain insights into consumer behavior to provide managerial implications on what fashion companies need to do to increase green trust during the transformation process towards sustainable development in order to increase green purchase intention. Two sub-research questions are raised to answer the main research question all- encompassing in the end. The sub-research questions aim at gaining theoretical knowledge about how consumers perceive corporate social responsibility (CSR) activities of fashion companies, including if they can detect companies in the transformation process and what creates trust concerning CSR activities, as well as identifying influencing factors of green trust.  Design/methodology/approach – Since this research aims to investigate complex constructs of consumer behavior, it takes an exploratory approach through qualitative research. Focus group discussions are chosen as the central research method. Data analysis is carried out using qualitative content analysis according to Kuckartz (2014) in order to systematically analyze the data material.  Findings – Five sources of green trust have been identified, which are traceability, brand image, material, transparency, and certificates. The factors green confusion, greenwashing, lack of information and lack of knowledge have been observed to cause green distrust among consumers. The results of the study show that consumers’ level of knowledge on the subject of sustainability in the fashion industry varies tremendously. In order to increase green trust and thus increase green purchase intention, educational measures must be taken by both companies and independent institutions. Moreover, companies need to conduct sufficient CSR communications that are easy to access, understand, and trustworthy.  Research limitations – This paper is limited to a time frame of nine weeks, which was given for the completion of the work. In addition, it is limited to the fact that qualitative research does not deliver statistically proven and representative results. For this reason, it is limited to the interpretation barrier, which states that results are at risk to be subjective.  Keywords – transformation process towards sustainable development, sustainable development in the fashion industry, green trust on the consumer side, strategic CSR, organizational change  Paper type – Master thesis