Deliberate self-harm was studied in 14-year-old adolescents from four schools in southern Sweden with a test-retest design, using a nine-item version of the Deliberate Self-Harm Inventory. At Time 1, 40.2% of the adolescents indicated deliberate self-harm on at least one occasion compared with 36.5% at Time 2. Test-retest data showed high stability over periods of up to 2 months in duration. Cross-validation of the results from Time 1 to Time 2 showed robust correlations between deliberate self-harm and general psychopathology, a relative absence of positive feelings toward parents, and a ruminative style of emotional regulation. Further, rumination/negative thinking and a relative absence of positive feelings toward parents were predictors of self-harm independently of general psychopathology. In addition, deliberate self-harm correlated with symptoms of eating disorder and negative body esteem in girls.