OBJECTIVES: To determine the patient factors influencing UK Emergency Department doctors' assessment of suicide risk. To establish whether immediate clinical management is consistent with perceived risk. METHODS: The Manchester and Salford Self-Harm project is a multi-centre deliberate self-harm monitoring study. Data collected were used to analyse risk assessments made by Emergency Department doctors between September 1997 and August 1999. We used univariate and logistic regression analyses to determine the factors Emergency Department doctors used to make suicide risk assessments. RESULTS: A total of 3220 deliberate self-harm assessment forms were completed in two years by Emergency Department doctors; 2922 (91%) included a clinical assessment of risk; 28 out of 48 variables were associated with perceived suicide risk. Multiple logistic regression analyses showed that current mental state, high suicidal intent (including medical seriousness of attempt), and male sex were the most important independent predictors of suicide risk. Being referred to psychiatric services directly from the Emergency Department or to surgical/medical services was also strongly associated with a perceived high risk. CONCLUSION: In contrast to the negative findings of previous research, we found that Emergency Department doctors were influenced by key risk factors for suicide in their assessment of deliberate self-harm patients. Emergency Department doctors' assessments reflected the immediate risk of suicide, indicated by factors such as current mental state and strong suicidal intent. Background risk factors such as social adversity and psychiatric history were less influential. We would recommend that training for emergency doctors should emphasize the importance of both immediate and background risk factors.