Entrepreneurial orientation (EO) has become a construct of considerable interest in the family business literature. Despite such attention, scholars have yet to examine if and how EO in family businesses changes over time. This study explores this gap by investigating both continuous and discontinuous changes in EO in a sample of S&P 500 family businesses between 2001 and 2012. We find that EO changes before, during, and after an environmental jolt, which is defined as a major unforeseen and discontinuous environmental change. More specifically, we find that EO gradually increases at a linear rate prior to the occurrence of a jolt, discontinuously decreases during the initial stage of the jolt, then resumes a gradual linear growth trend following this period. We further explore the relationship between time and EO by examining change in EO across different industries, finding significant changes between family firms in different industries.