Project Summary (max 30 lines text) Individuals’ work conditions are strongly related to their health. Parents’ work conditions can also affect the health and development of their children, who are greatly influenced and constrained by their parents’ lived experiences in the labor market. Work schedules are a particularly underexplored aspect of work conditions, with the potential to shape worker and family health. The importance of understanding scheduling’s effects continues to increase as low-wage employment shifts toward the service sector, with its characteristic variability and unpredictability in work and pay. Prior research has shown that work schedule unpredictability is common among low- wage workers and that it is associated with worse worker and family well-being. Despite this emerging body of evidence, however, there remain a number of unknowns. First, although schedule unpredictability correlates to worse outcomes for workers and families, it is unclear from the extant literature whether schedule unpredictability causes worse outcomes or whether the associations merely reflect differences between workers in other characteristics that predict both schedule unpredictability and worker well-being. Second, while policies regulating work often connect rhetorically to community-level population health, laws aimed at curbing schedule unpredictability for low-wage service workers are very new and little is known about the health effects, intended or unintended, of such legislation. The proposed research project will address these gaps in the literature by using an innovative daily diary methodology to gather daily reports from 1,000 low-wage working parents about work schedule unpredictability, pay, and worker and family mental health. Daily reports will be gathered over two one-month periods, once prior to a schedule stability law taking effect and once after the law is implemented. We utilize a unique daily survey tool that our research team created and extensively piloted. No other researchers examining work conditions and family health are utilizing this type of data collection method. Because our design combines a daily diary study with the implementation of a policy change, we can both examine the causal within-family effect of daily unpredictability on worker and family health and also identify causal effects of regulation that changes work conditions. Studies of work conditions and worker health typically rely on between-person survey approaches. Our design effectively utilizes within-person change over time both day-to-day and between periods to investigate the causal effect of work schedule unpredictability on health.