A sizable body of research has established work-family conflict and its nomological network. Despite decades of research, we have yet to form a precise understanding of what happens when a conflict arises. The current research addresses this question using a growth modeling, episodic approach. We use stressor-strain and allostatic load theories to examine changes in daily patterns of psychological (fatigue, negative affect) and physiological (heart rate, blood pressure) strains that occur during and after a work-family conflict episode. We found some evidence for acute changes in psychological strain during and after work-to-family conflict episodes. Daily family-to-work conflict was associated with mixed reactions. State fatigue and heart rate decreased at the time of a family-to-work conflict, although state negative affect increased at the time of family-to-work conflict, and state fatigue increased more rapidly throughout the day after the second time family-to-work conflict was experienced. Additionally, we found evidence that state negative affect increases throughout the day as work-to-family conflict episodes accumulate. Daily family-to-work conflict accumulation was also associated with decreased fatigue, increased state negative affect, and increased systolic blood pressure. Lagged analyses showed some evidence that negative mood predicts work-family conflict occurrence within the next few hours. Implications for the theoretical relationship between work-family conflict and strain are discussed. (PsycInfo Database Record (c) 2020 APA, all rights reserved).