This study examined within-person co-occurrence of self-focus, negative affect, and stress in a community sample of adolescents with or without emotional disorders. As part of a larger study, 278 adolescents were interviewed about emotional disorders. Later, they completed diary measures over three days, six times a day, reporting their current thoughts, affect, and levels of stress. Negative affect was independently related to both concurrent stress and self-focus. Importantly, the association between negative affect and self-focus was stronger among participants with a recent unipolar mood disorder, compared to those with an anxiety disorder, comorbid anxiety and depression, or those without an emotional disorder. The implications of these findings to theories of self-focus and its role in emotional disorders are discussed.