Abstract: Functional clothing refers to a genre of clothing that is developed to meet very specific and niche requirements of the end user. It is a result of interference of multiple domains of product development, such as technical textiles and other construction technologies. There are four basic requirements of any functional clothing namely physiological, biochemical, ergonomic and psychological. This paper focuses on the requirement-based classification of sportswear properties and how they have been used to improve the performance of the sportsperson.