Introduction: Research has shown that family firms play an important role in modern economies and that they maintain special characteristics and features in comparison to non-family businesses. Furthermore, it is evident in literature and practice that internationalization is a crucial process and strategy in the present global business environment.

Problem: These findings however, have not led to a family business internationalization strategy. Only some studies have been conducted concerning the influence of the special features of family firms on the process of internationalization. This means that there is a gap between theory and practice.

Purpose: To increase the academic understanding of the phenomenon internationalization of family businesses, through the use of both theoretical and empirical findings.

Research questions: This study attempted to fulfill the purpose by providing answers to several research questions. The main research questions are: What is the current state of knowledge about internationalization, family business features and previous research in internationalization of family firms? How do the family business features theoretically influence the internationalization process? How do the family business features empirically influence the internationalization process? What are the theoretical contributions and practical managerial implications of these findings?

Method: A solid literature research has been conducted in order to determine the theoretical influences of family business features on internationalization. The empirical testing of the expectations was conducted through a qualitative approach by taking personal interviews at eight companies, four in The Netherlands and four in Sweden, and studying secondary documentation.

Findings: The study shows that it is difficult to decisively determine the either facilitating or constraining influence of family business features on internationalization. The results show that the 23 features which have been studied in the sample are facilitating or constraining under certain conditions (see table 5, p. 108). This implies that managers, researchers and consultants will be required to study these conditions first in order to determine the facilitating or constraining effects in a company. In addition, a model has been constructed illustrating the empirical findings concerning the internationalization process (see figure 8, p.112). Finally, concerning internationalization theories, it is determined that family businesses tend to use the Network approach in starting their internationalization process, the Stage approaches in further developing the international operations and support their process through the Resource-based view and the Knowledge-based view.