Human physiology and behavior are deeply rooted in the daily 24 hour temporal structure. Our biological processes vary significantly and idiosyncratically throughout the day. Continued disruption of biological rhythms often has serious consequences for physical and mental well-being, causing cardiovascular disease, cancer, obesity, and mental health problems. My research goal is to advance a vision for \circadian computing" | designing, developing and deploying novel technology that helps to maintain our innate biological rhythms. Towards that vision, I focus on developing technologies for detecting circadian disruptions and providing in-situ interventions. My approach involves passive and automated sensing of behavioral traits to model body clock patterns that can be used to support varying needs of users over time. One strand of my research focuses on developing tools that can adapt to our individual rhythms and provide more biologically attuned support in the areas of physical and cognitive performance, sleep, and wellbeing. The other aspect of my research focuses on mental health | preventing relapse by identifying disruptions and providing circadian interventions for bipolar and schizophrenic patients.