The aim of the study was to explore the predictive validity of the Suicidal Scale of the Mini-International Neuropsychiatric Interview as a screen for suicidal behavior and non-suicidal self-injury following discharge from an acute psychiatric ward. Using a prospective, naturalistic design, the patients were screened with the Suicidal Scale when discharged (n = 307). At 12 months post-discharge, the Suicidal Scale was a significant predictor of suicidal behavior (n = 48) and suicidal behavior+non-suicidal self-injury (n = 49) but not for non-suicidal self-injury (n = 15). For patients without any known previous suicide attempts (n = 180), the Suicidal Scale was a significant predictor of suicidal behavior (n = 21) and suicidal behavior+non-suicidal self-injury (n = 11). Further research is needed to determine the overall utility of the routine screening of self-harm.