Middle childhood represents a key transition period following the rapid changes of emerging autonomy in early childhood and processes of individuation during adolescence. Yet little is known, particularly for children living in poverty in rural contexts, about the ways in which specific developmental trajectories established in infancy and early childhood support or constrain self-regulation abilities required to successfully navigate this period of the life course. The overarching contribution of the Family Life Project is to address how experiences of middle childhood serve to promote continuity versus discontinuity in development, both to increase risk for adverse outcomes as well as to enhance capabilities and to promote positive development. During middle childhood, children face significant new challenges and become increasingly self-directed in choices relating to activities, friendships, and school, with increasing demands on self-regulation. This may be particularly so for children growing up in low income, rural communities; however, very little is known about the experience of children in these contexts. To address pressing issues in development in middle childhood. Project I of the FLP continues to focus on the measurement of key aspects of self-regulation including executive functions (EF), emotion regulation (ER) as well as stress response physiology including salivary Cortisol and salivary alpha amylase (sAA) as children develop Also, we examine pubertal timing, temperamental emotional activity, race, and gender, as potentially highly salient child level characteristics that will be central to understanding associations among adversity, self-regulation, and mental health outcomes. Critical to our enquiry in this third phase of the project are questions about the ways that rural contexts in which children are developing might accentuate or perhaps in some cases deflect risk associated with race, poverty, and child characteristics. In particular, we are interested in the extent to which opportunities for change may be limited by high levels of social and economic stratification in more geographically isolated communities characterized by high rates of poverty, unemployment, and low social capital. As such, we continue to focus on the careful and comprehensive measurement of self-regulation and do so with the express purpose of understanding the extent to which self-regulation difficulties may be more frequent in families facing high levels of poverty-related adversity and more likely to lead to disadvantageous outcomes in smaller, more highly stratified rural communities. In keeping with the child x environment perspective that organizes the study of development in the FLP, we are interested in how children's self-regulation capacities interact with the constraints and affordances imposed on their actions, behaviors, and choices by the contexts of their daily lives, including characteristics of classrooms, peer groups, neighborhoods, and communities. Major areas of innovation in this phase of our research include 1) the longitudinal measurement of self-regulation abilities in an area of developmental science in which few such studies have been conducted and 2) the detailed examination of child stress physiology, including reactivity and regulation of the sympathetic (sAA) as well as HPA (Cortisol) systems in response to a moderate stressor. Additional areas of innovation include 3) the modeling of poverty-related adversity longitudinally to test a model whereby measures of stress physiology(cortisol and sAA) and self-regulation (EF, ER, sensitivity to reward) mediate effects of family adversity and the timing and duration of poverty on child outcomes; and 4) the ways in which rural context moderates risk associated with self-regulation difficulties in the prediction of child mental health outcomes. We propose to test a model by which adverse experiences in early and middle childhood are associated with alterations to stress physiology in ways that are hypothesized to constrain the development of self-regulation, thereby increasing the likelihood of emerging externalizing and internalizing psychopathology. Critically, using hierarchical linear modeling, we propose to examine cross level interactions in which we test our key hypotheses concerning the extent to which characteristics of rural contexts, including classroom, peer, neighborhood, and community characteristics increase risk for poor mental health outcomes associated with self-regulation difficulties. To our knowledge this is the first study of its kind to test these complex longitudinal relations between adversity, self-regulation, and mental health outcomes across multiple geographically and economically defined social contexts in a population-based sample.