We draw on the Effort-Reward-Imbalance (ERI) Model to examine factors related to the development of burn-out symptoms as well as the consequences of burn-out. Our sample consists of 168 small and newly founded business ventures. Our results indicate that physical well-being is negatively related to the development of burn-out symptoms. Moreover, burn-out is negatively related to operational performance. Finally, we found some indication of the type of entrepreneur affecting both the relationship between physical well-being and burn-out, and between burn-out and operational performance. Specifically, we found higher correlations among necessity- and opportunity-driven entrepreneurs as compared to rationality-driven entrepreneurs.