Complete garment knitting technology is a method of producing knitted products, generally fashion garments, ready-made directly in the knitting machine without additional operations such as cutting and sewing. This makes it possible to manufacture a knitted fashion garment with fewer processes then with conventional production methods. In the fashion business customer demand is always changing due to fashion trends, so to be able to manufacture and deliver products rapidly is important. Mass customisation is a customer co-design process of products and services that tries to meets the needs of an individual customer’s demand for certain product features. In the fashion business this means that the customer can order a garment with a customised style, colour, size, and other personal preferences. The principal objective of this dissertation was to examine if and how complete garment technology can be applied to the customisation of knitted fashion products. It was pursued through several independent studies in knitting technology, mass customisation, and fashion logistics against a theoretical frame of reference in these areas. The papers in this thesis present various examples of how knitted fashion garments can be customised and integrated into fashion retailing concepts. The starting point of the research was the Knit-on-Demand research project conducted at the Swedish School of Textiles in collaboration with a knitting manufacturing and retailing company. The aim was to develop a shop concept built on the complete garment technology where a garment could be customised, produced, and delivered as quickly as possible. This initial idea failed due to the expense of investing in complete garment knitting technology, and so other avenues of research had to be found. The Knit-on-Demand project continued, using a business model similar to the complete garment concept but with the retail store and the production unit situated in different locations. The overall research question addressed in this thesis is: How can complete garment knitting technology be applied in a retail concept for customised garments? This question is then divided in two problems: What are the fashion logistics effects of combining complete garment technology and mass customisation? How does the co-design process function in the customisation of knitted fashion garments?The following is a qualitative study based on five research articles applying different research methodologies: case studies, simulations, and interviews. The empirical context is the area of mass customisation of fashion products and knitting technology, more specifically called complete garment knitting production technology. No prior studies describing mass customisation of complete garment knitting technology in combination with fashion logistics were found in the literature. The main contribution of this study is the demonstration that complete garment knitting technology can be applied in the customisation of fashion products. It also illustrates the importance of the co-design process between the company and the customer through which a knitted garment can be customised, produced, and delivered to the customer in three to five hours. The process of co-design and manufacture of a customised complete fashion product is examined, and the advantages and disadvantages associated with customisation of knitted garments are identified and described.