Although distribution and warehousing theory have been extensively studied in terms of optimisation and functional excellence the extension of these concepts into supply chain management has not been fully explored. In addition information at which decision level warehousing strategies are formed is limited. The purpose of this thesis is to investigate which supply chain drivers and subordinate variables that affect warehousing decisions and how these can be used for warehousing strategies. The findings will serve as a decision support in strategic warehouse network design. To fulfil the purpose of the thesis a case study was performed at a sportswear company contributing to the textile and apparel focus of the research. The case company is facing a potential restructure of its warehousing network as the current distribution strategy has created different constraints and complexities which have lead to problems. Through a literature review important supply chain drivers as well as warehousing variables have been identified and serve as the basis for the case company investigation conducted using interviews and a survey. The empirical findings contribute to the results by determining whether decisions regarding the variables are on a strategic, tactical or operational level. The result is a Decision Support System integrating supply chain drivers, warehousing variables and decision levels. The framework fills gaps found in the literature by defining different decision levels of warehousing and by integrating warehousing in the supply chain strategy. The Decision Support System is subsequently applied to the case company revealing areas which need to be considered and improved prior to a restructuring of its warehousing network. By using the Decision Support System a textile and apparel company can map its supply chain and warehousing strategy revealing strengths and weaknesses in the network. The Decision Support System facilitates decisions regarding warehousing and simplifies the process of moving from the strategy employed to the best practice strategy thereby increasing customer satisfaction and achieving a competitive advantage. / Program: Textilt management med inriktning styrning av textila värdekedjor