Objective: Suicidal ideation and suicide attempts are important indicators of extreme emotional distress. However, little is known about predictors of onset and course of suicidality in the general population. Our study tried to fill this gap by analyzing data from a prospectively followed community sample. Method: Data were derived from the Netherlands Mental Health Survey and Incidence Study (NEMESIS), a 3-wave cohort study in a representative sample (n = 4848) of the Dutch adult general population. Results: The 3-year incidence of suicidal ideation and suicide attempts was 2.7% and 0.9%, respectively. Predictors of first-onset suicidal ideation and suicide attempts were sociodemographic variables (especially the negative change in situation variables), life events, personal vulnerability indicators, and emotional (mood and anxiety) disorders. Comparison of the corresponding odds ratios and confidence intervals revealed that predictors for first-onset suicidal ideation and suicide attempts did not differ significantly. One of the strongest predictors of incident suicide attempts was previous suicidal ideation. Regarding the course of suicidal ideation, it was found that 31.3% still endorsed these thoughts and 7.4% reported having made a suicide attempt 2 years later. Conclusions: Similar predictors were found for first-onset suicidal ideation and suicide attempts. This suggests that suicidal behaviours may be ordered on a continuum and have shared risk factors. While suicidal thoughts may be necessary for, they are not sufficient predictors of, suicidal acts. The course of suicidality in the general population can be characterized by a minority of people having suicidal experiences that develop over time with progressively increasing severity.