The Child Health Study (CHS; Shenk, Co-I) is an NIH-funded (Noll, PI: P50HD089922) state-wide, prospective cohort study examining the impact of child maltreatment on multiple biological systems and subsequent pediatric health. One of my laboratory’s contributions to the CHS is the use of observational methods to quantify caregiver-child dyadic communication and establish how specific patterns of communication are involved in promoting resilience to adverse health following exposure to child maltreatment. Caregivers and their children participating in the CHS (N=500 and counting!) complete three separate interaction tasks designed to promote relationship quality and dyadic problem-solving. Caregiver-child communication is then sampled using a multilevel, intensive longitudinal design, where specific processes are quantified in 30-second epochs to estimate dynamic change within and across tasks. Furthermore, families in the CHS complete waves of data collection every two years with the same three interaction tasks administered at each wave, allowing for inferences about how specific caregiver-child communication patterns change from childhood to adulthood and in response to child maltreatment. Following a deep phenotyping and multiple levels of analysis approach, data obtained from these observational methods will ultimately be included with biological, behavioral, and other environmental mechanisms of adverse health being measured in the CHS, such as structural and functional MRI, genome-wide DNA methylation, immune function, cognitive development, psychiatric function, and more. T32 Fellows will have the opportunity to learn observational methods, quantify dyadic communication processes, and link changes in communication processes to putative mediators and psychiatric outcomes.