There are three are three official city regions in Sweden at the moment. This thesis investigates the process to create a fourth, the development of Linköping and Norrköping, twin cities strategically placed in reach of the other three metropolitan areas. Strategic planning implies a perspective where different instruments and indicators which complements or contradicts each other. The importance of the collaboration between different plans could have synergetic or cumulative effects. Urban development is a progress over a long time period and the infrastructural projects will have even longer effects. Environmental assessments like EIA and SEA and other methods, which are used in different parts of strategic planning, aims to identify and reveal goal conflicts. They also discuss alternatives and unsustainable effects as a base for decision making. Sustainable development can be seen as a goal or a process, both perspectives is highly dependent on of infrastructure and other physical structures in the society. The results of this study express an urgency of transition towards a more cautious attitude towards the future development. The alignment of regional development that can be followed through out the investigated plans shows a strong focus of economic growth, rather than finding sustainable solutions.