This thesis is about how to design Computer Supported Cooperative Work systems (CSCW) on the basis of design practice that is established in the Scandinavian model of System Design. The approach of the thesis is to develop an understanding of the design of CSCW environments through a series of case studies. These case studies, the CoDesk system, the AtWork system and the VideoCafe system, cover a variety of methods from the Scandinavian tradition in cooperative design. Studying how these methods have succeeded has been the primary source of inspiration for my thesis. In particular, this thesis will focus on the following issues: Can simulation of realistic work situations be used for cooperative design of CSCW systems by developers and users? And, how can we balance a design based on daily work practice with exploration of innovative CSCW solutions? Furthermore we are also investigating how cooperative design could be integrated in the evolving use and how to combine different design approaches into a coherent design. Given the complexity of CSCW it will be argued that the design of CSCW system needs to mix design methods with various backgrounds, such as methods that have their roots in workplace practice with methods that transcend common styles of cooperation, to balance different design methods' strengths and weaknesses. It is suggested that a usable approach is to define and use different design orientations in order to deal with this complexity. The use of a design orientation helps in selecting the essential element that is at the heart of the design. This approach seems more usable than working with pure design methods with specific outlines. A design orientation integrates instead a holistic view into the design by leaving the pre-dominant sequential notion in system modeling.