There has been an increase of the consumption rate and consumers are buying garments that they dispose in too early of a stage of the product lifecycle. This has caused an increase regarding landfill of waste. The aspect of implementing environmental oriented material science and garment technology has not been taken into consideration in the design process, something that quickly became an issue when the consumption rate increased. Therefore it is essential to rethink and restructure the business models applied today. The implementation of a circular economy, which focuses on giving textiles and garments a second life and basing production on used fibres whilst not harming the natural resources in the process, is a good start of the long journey to recovery which lies ahead. Both fast fashion companies and premium lifestyle brands are nowadays applying and integrating new business models into their daily operations, Tommy Hilfiger is an example of such a company. Purpose: The purpose of this thesis is to explore the relationship between material science, garment technology and the concept of circular economies from a premium lifestyle brand perspective The researcher will explore how material science and garment technology can prevent faulty items and short product lifecycles. Furthermore, the researcher will investigate how a company develops underwear collections with regards to material science, garment technology, and the concept of circular economies. The company Tommy Hilfiger will be implemented as an exponent throughout this report. Research questions: • What is the relationship between material science, garment technology, and the concept of circular economies? • What does a premium lifestyle brand take into consideration regarding the concept of circular economies when developing a collection of underwear? Methodology: This thesis was conducted by applying a qualitative method and by implementing a deductive approach. The gathering of secondary data was done through assembling suitable concepts and theories. The researcher collected the primary data through a participating observation and four qualitative interviews. The participating observation corresponded of an internship at the European headquarters of Tommy Hilfiger in Amsterdam, Netherlands. The researcher executed the interviews via email with key people within the departments of Design, Production, Central Sourcing and Production, and Corporate Responsibility. Conclusion: Material science and garment technology are correlated given that the choice of material and manufacturing technique utilized in production determines the durability and sustainability level of the fabric output. Therefore the two concepts are further correlated to the product aspect, which can enable a closed textile value chain loop, of a circular economy based business model. A premium lifestyle brand takes the aspects of design out waste, build resilience through diversity, work towards using energy from renewable sources, and think in consecutive processes into consideration regarding the concept of circular economies when developing a collection of underwear.