There is not just one official definition of sustainability, but instead over three hundred. Previous studies together show tendencies towards a possible gap in the consumer versus company definitions of sustainability in apparel. A gap in how sustainability is defined. This thesis aims to contribute to the filling of this possible gap with a description and analysis of the matter. Deep semi structured interviews with ten female fashion consumers from the conscious Generation Y, defining and discussing sustainability were performed. The same consumers also attended a one-hour focus group session. The consumer definitions of sustainability were compared with the definitions from Gina Tricot, H&M, Kappahl, Lindex and MQ via their sustainability reports. Our findings shows several gaps in the way sustainability was defined by the conscious female fashion consumer from Generation Y and the conscious fashion company presenting a sustainability report. The two main gaps are the consumers defining sustainability as long lasting quality and less consumption. The companies in their sustainability reports do not address these definitions. Communication, deeper interaction and enhancements in the business model supply chains are concluded in order to address the gaps. For further research a larger more extended study could enhance the results and give deeper insights.