This thesis is concerned with the work of business leaders. The interest lies in the holders of positions as Chairpersons, Boardmembers and Managing Directors. This study, however, goes beyond the position holder to consider the actions of actors, as they operate within networks with concurrent multiple business activities. The purpose is to generate knowledge and understanding of the activities and relations of multibusiness leaders involved in managing small and medium-sized companies. Major schools of thought on the manager's job are described. The review relates the scientific debate about different schools and emphasises the need for more inductive research. The call for processual and contextual analysis leads to an epistemological position grounded in understanding through interpretation. The method used in this study adopts such an approach, and thus aims to discover qualities of the studied phenomenon based on social constructivism. Empirical reality is approached by means of intensive studies of a few cases. Case descriptions of the work of multibusiness leaders in the National, Regional, Intermediary, Independent, and Developing Networks are undertaken, where the inter­action processes of the different actors are described according to the working life his­tory of the actor, and to the networking and work activities carried out. The analysis is based upon four themes (the actor's 'task legitimacy', 'economic legi­timacy', 'idea development' and 'network'). The first two themes have been given the generic term 'legitimacy concept', not only to reflect the interactive and changeable aspects of work, but also to illustrate how work in itself is intimately interwoven in an institutional context. The creation of 'task legitimacy' and 'economic legitimacy' of the leaders is analysed. The analysis of the actors' idea development results in a description of differing visions in the individual networks. This description takes up visions covering long-term industrial leadership, regional co-operative leadership, restructuring leadership, flexible market-adaptive leadership and network-based leadership. In a survey of the existing literature, the role of a leader is seen as one of many managerial roles, a view that is based upon the work of Mintzberg (1973). This study contrasts with the above picture, by discussing a reciprocal dependency between the leader's leadership role and his/her other roles. This reciprocity and concurrency is dealt with by introducing the concept of identity as a theoretical aid, thus reflecting in a more appropriate way the complex and interactive actor. The social identity concept (Tajfel, 1982) is used, in order to answer more profoundly the research questions. As leaders are reciprocally dependent on a network for their own existence, we must both look inward in order to be able to understand at a deeper level the actors' motives, and look outward to be able to look at identity creation in a wider industry context. What I have termed näringslivsledaridentitet (the Identity of Multibusiness Leaders), is a substantial part of this study's findings. The concept is used in order to be able to describe how the actors' inner and outer motives merge in identity creating processes. The actors' different patterns of interaction are absorbed into a composite whole. / digitalisering@umu