Stress is an everyday phenomenon. The effects of stress become manifest on multiple levels, including behavior, subjective experience, cognitive function, and physiology. Recent imaging studies using a stress paradigm for the fMRI environment have shown a specific brain activation pattern under stress, characterized by deactivation in limbic areas. The Trier Social Stress Test (TSST) has become the gold standard for the experimental induction of psychological stress. This chapter focuses on studies that have used the method of intranasal administration, which in recent years has been successfully combined with established behavioral and neuroimaging paradigms to clarify oxytocin's (OXT's) actions in the human brain. Overall, the tremendous growth in this research field offers not only a promising new path for exploring the neuroendocrinology of the social brain but also a translational perspective for developing novel treatment strategies for social disorders.