BACKGROUND: Hopelessness is frequently observed in people who harm themselves and is an established risk factor for nonfatal self-harm repetition and suicide. Little is known about how the presence of hopelessness in addition to other risk factors affects subsequent risk. METHOD: Prospective cohort of 19,479 individuals presenting with self-harm to one of three English Emergency Departments between 1st January 2000 and 31st December 2010. Repeat self-harm and suicide deaths within twelve months of the first assessed episode were identified. Cox Proportional Hazards models were used to estimate Hazard Ratios (HRs) for risk factors with and without hopelessness. RESULTS: A clinical impression of hopelessness was associated with increased risk of further self-harm (HR 1.35, 95% CI 1.16-1.58) and suicide (HR 2.56, CI 1.10-5.96) in the year following an index episode. For individuals who were living alone or homeless, unemployed, reported problems with housing, had received psychiatric treatment in the past, were currently receiving treatment or used alcohol during the self-harm episode, an exacerbation of an already elevated risk of repetition was observed amongst those who were assessed as hopeless. Where individuals presented with forensic problems, physical health problems or bereavement, an increase in risk was only observed for those who were also assessed as hopeless. LIMITATIONS: A clinical impression of hopelessness was assigned using a binary "yes"/"no" classification rather than a validated scale. CONCLUSIONS: Hopelessness intensifies the impact of several known risk factors for adverse outcomes following self-harm. These findings highlight the importance of identifying and therapeutically addressing this dynamic but potentially modifiable clinical risk factor during the psychosocial assessment and in subsequent care.