OBJECTIVE: A better understanding of the pathophysiology of suicidal behaviour (SB) may enable the discovery of more specific treatments and a better identification of vulnerable patients. The vulnerability to SB appears to be underlied by genetic factors coding for traits rendering the individual less able to cope with stressing situations, and more likely to be engaged in a suicidal process. METHOD: During the recent years, neuroscientific studies begun to identify potential endophenotypes. RESULTS: We have shown that disadvantageous decision making (DM) was involved in the vulnerability to SB. DM impairment appears to be independent of comorbid psychiatric disorders, associated with emotional dysregulation (i.e. affective lability trait and skin conductance responses), and modulated by serotonergic genotypes associated with SB. In recent fMRI studies, the region that is likely involved in DM, is overactivited in response to angry faces, suggesting a higher sensitivity to specific negative social stimuli. Deficit in risk evaluation and excessive response to specific emotional stimuli may represent key processes in the vulnerability to SB. CONCLUSIONS: These potential endophenotypes may represent future relevant markers of vulnerability for the identification of vulnerable patients, and relevant targets for the development of new treatments.