Stress contributes to the onset and development of disorders like anxiety, depression, and posttraumatic stress disorder (PTSD). However, some individuals are more vulnerable to the adverse effects of stress whereas others are more resilient. We want to understand the biological factors that contribute to stress resilience/vulnerability and why they might differ among individuals. We model stress resilience and vulnerability in the lab using the Chronic Social Defeat Stress paradigm (CSDS), in which resilient and vulnerable subpopulations can be easily identified. We use chemogenetic approaches and a wide range of molecular assays to understand how specific neural circuits and transcripts differ in these subpopulations.