For a solution to the family business definition dilemma, we propose the application of a scale that assesses the extent and the quality of family influence via the measurement of three dimensions: Power, Experience, and Culture. The Family Influence on Power, Experience, and Culture (F-PEC) scale is tested rigorously, utilizing a sample of more than 1,000 randomly selected companies, through the application of exploratory and confirmatory factor analytic techniques. The scale demonstrates high levels of reliability. F-PEC has been applied in a number of studies, contributing to theory development, particularly in terms of the impact of family influence on distinct resources, and as a source of competitive advantage.