Childhood adversity is a leading transdiagnostic risk factor for psychopathology, being associated with an estimated 31-62% of childhood-onset disorders and 23-42% of adult-onset disorders (Kessler et al., 2010). Major unresolved theoretical challenges stem from the nonspecific and probabilistic nature of the links between childhood adversity and psychopathology. The links are nonspecific because childhood adversity increases risk, through a range of mechanisms, for diverse forms of psychopathology and are probabilistic because not all individuals exposed to childhood adversity develop psychopathology. In this article, we propose a path forward by focusing on stress phenotypes, defined as biobehavioral patterns activated in response to stressors that can disrupt future functioning when persistent (e.g., reward seeking, social withdrawal, aggression). This review centers on the accumulating evidence that psychopathology appears to be more strongly predicted by behavior and biology during states of stress. Building on this observation, our theoretical framework proposes that we can model pathways from childhood adversity to psychopathology with greater specificity and certainty by understanding stress phenotypes, defined as patterns of behavior and their corresponding biological substrates that are elicited by stressors. This approach aims to advance our conceptualization of mediating pathways from childhood adversity to psychopathology. Understanding stress phenotypes will bring us closer to "precision mental health," a person-centered approach to identifying, preventing, and treating psychopathology. (PsycInfo Database Record (c) 2023 APA, all rights reserved).