Samenvatting

This dissertation concerns the adaptive ability by which workers meet new expertise needs throughout their careers. We aimed to increase our understanding of this adaptive ability through a series of four studies building upon the concept of flexpertise (Van der Heijden, 1998, 2000). These studies were designed to advance theorizing, specifically in scholarly research on expertise and expert performance (Ericsson et al., 2006) and sustainable careers (Van der Heijden & De Vos, 2015), and to increase our understanding of how flexpertise may be fostered among workers across expertise domains and working contexts.In this introduction chapter, we outline the key theoretical concepts regarding the flexpertise phenomenon that we will use throughout this dissertation, a description of the knowledge gap in the scholarly literature, and our research focus. This is followed by a summary of this PhD project that outlines the overall research objective, the research questions and research methods that we deployed, as well as an overview of the four flexpertise studies conducted (see Table 1.1). The subsequent chapters include the four (submitted) scientific publications on this matter. We conclude by reflecting on the theoretical, methodological and practical value of our research, and on the limitations of our research approach. We finish with recommendations for future research, ethical considerations on the usage of the flexpertise concept in labor market debates, and a personal reflection on this PhD program.Before explaining the key concept of flexpertise and related core concepts, we first outline what we mean by new expertise needs. These needs shaped the background of the four studies conducted.