Anotace:
This paper determines the profile of a family business that ensures the greatest engagement of family members in running a family business and has the strongest impact on the competitiveness of such an enterprise and its organisational effectiveness. The theoretical part addresses organisational effectiveness. It emphasises the variety of criteria and areas of its assessment and the relationships between organisational effectiveness and competitiveness. It discusses familiness as a unique resource and competitive advantage of family businesses. The analytical part presents the research methodology, including the authors’ formula for calculating the measure of familiness and the procedure for identifying the profile of a family business, ensuring the greatest familiness engagement in business activities, which affects the organisational effectiveness and competitiveness of family businesses. This procedure was based on applying the gray system theory (GST). The research was based on the incomplete numerical induction method on a targeted sample of 200 family businesses operating in Poland that met the research criteria. The results show that the features most responsible for the highest engagement of familiness in the family enterprise are the territorial scope and size of the company, and the age of the family member involved in the activities of the enterprise. Small and medium-sized enterprises operating on the domestic market, in which a family member aged 36-45 is involved, generate the highest level of familiness in all seven researched areas of organisational effectiveness, including in the area of goals, and also generate the highest level of competitiveness of family businesses.