The objective of this dissertation is to determine how an entrepreneurial individual, either alone or as part of a team, contributes to the development and sustainability of a start-up venture. It is well-recognized that the entrepreneur or business owner is a powerful organizational driver, whose ideas and vision affect the start-up through the articulation of strategy, the allocation of resources, and the definition of organizational tasks. Conversely, relatively little empirical evidence directly corroborates business owner characteristics, such as human capital and social capital, as the mainstay of a new venture. Besides, prior research that does focus on the significance of powerful actors within the firm usually adopts a unilateral performance lens. There is much debate on what constitutes an adequate performance measure, especially when it comes to capturing start-up functioning. Consequently, research on start-ups within this strand of literature has been scant, while a clear need exists for other constructs that accurately reflect new venture operation. In order to examine a business owner s human and social capital contributions to start-up development and sustainability, we employ four distinct operationalisations: the start-up s ability to acquire, assimilate and exploit information; its volume of international sales; the strength of the entrepreneur s decision to remain self-employed; and the organization s capacity to generate value added. Flemish start-ups form this study s empirical setting.Our findings endorse specific business owner characteristics as basic levers of start-up development and sustainability. Evidence emerges that human capital mainly affects organizational outcomes if it is grounded in pertinent life-built experiences (start-up, industry, and management experience). This dissertation also shows that the impact of business owner human capital on start-up development and sustainability is context-contingent. Within our research design, the environmental situation of the start-up, the organization s accumulated knowledge base, and the distribution of experience within a founding team all add to the situated relevance of the owner s human capital. Apart from this human capital situatedness , we find proof of a positive impact of human capital relatedness , which determines the unique and inimitable character of the start-up s competitive advantage. From a policy-making perspective, we develop a human and social capital-induced definition of the term open entrepreneur , being a knowledge-driven entrepreneurial individual with an international state of mind that is expected to advance the knowledge-transformation of the Flemish economy. Additionally, evidence is provided on various distinct demographic and career-related obstacles to self-employment longevity, a recurrent stumbling block for the Flemish region. Summarizing our social capital findings, we can only marginally confirm the (often anticipated) direct organizational relevance of owner social capital. One could, therefore, argue that given the limited weight their social capital exerts on start-up development and sustainability, business owners should focus on building other entrepreneurial capital, such as expertise and know-how. However, social capital might function as a critical gateway for scarce, venture-related information which, in turn, could foster the further development of the business owner s human capital. Also, there exists a variety of organizational outcomes outside the scope of this dissertation, for which the business owner s social capital may actually be a robust predictor. Throughout this dissertation, we thus highlight avenues for future research while being mindful of a number of choices that had to be made.status: publishe
