This dissertation addresses the topic of manufacturing network strategies, with a particular focus on the plant perspective. Research on manufacturing networks aims at contributing decision support on how to set up and how to coordinate factories that act in a global setting. Manufacturing networks are networks consisting of wholly owned plant, as opposed to supply chains management where also plants belonging to other organisations are considered. Research on the role of the plant in manufacturing networks can help to gain insights in how the network works and how to achieve network-related competitive advantages. Over the last two decades there has been a trend in increased globalisation and when companies expand beyond their home markets there is a leap in complexity that needs to be handled. A survey of Swedish plants shows that a large majority of medium and large sized plants are part in some kind of manufacturing network, making research on such networks highly relevant. The overall objective of this dissertation is to investigate how factories fit into the network in terms of roles, strategic autonomy and market configurations. Much research has either focused on networks as a whole, often assuming similar or identical plants, or the focus has been on plant internal decision. This research addresses the borderland between plant and network. This dissertation addresses two research objectives. The first is to investigate the relationship between networks and plants roles with particular focus on Swedish based networks and plants and the second is to test and further develop the theory on plant roles. The empirical data that was used in the dissertation was the product of a mail survey and a case study at a manufacturer of heat exchangers. The survey was sent to 563 Swedish factories and included information on competitive priorities, processes, plant roles, performance, suppliers, risk as well as general product and company information. Using focus groups, the case company was followed from the start of the project in January 2006. Following the case company during five years gave the opportunity to study networks in transformation. The research contributed to several insights to the area of plant roles and manufacturing networks as well as to practitioners in manufacturing. Internal and external suppliers are handled differently in terms of selection criteria, which indicates different roles in the network. Detailed exploration of individual site competences has lead to an improved model based on competence themes and links between the plant level and the network level have been established. Additionally we contribute to the manufacturing strategy process area by investigating and suggesting a model for strategic decision autonomy in manufacturing networks. The results are aimed at providing guidance for decision making in manufacturing networks as well as providing an improved foundation for further research in the area.