Therapeutic research on suicide was virtually unknown a decade ago, but recently a great deal of clinically important information has emerged. A landmark event was approval by the US FDA of antisuicidal effects of clozapine in schizophrenia patients in 2003. Interest in effects of psychotropic drug treatments on suicidal behavior was strongly stimulated by recent regulatory warnings of increased risk of suicidal thoughts or behaviors in juveniles and young adults treated with modern antidepressants. This presentation reviews recent research findings pertaining to effects of psychoactive drugs on suicide risk. Antipsychotics other than clozapine are not known to reduce suicidal risk. Lithium has compelling evidence of long-term effectiveness in reducing risks of suicide and attempts by as much as 80% among patients with bipolar disorders, a mix of major affective disorders, and possibly also recurrent major depressive disorder. It has long been recognized that some depressed patients experience increased agitation soon after exposure to antidepressants, and such reactions may increase suicidal risk. These effects usually can be anticipated and minimized by timely clinical interventions. The findings of beneficial effects of antidepressant treatment on suicidal ideation but not behavior, and of reduced risk of suicidal behaviors by lithium and clozapine, suggest differential pharmacologic effects on particular components of 'suicidality,' in that reduction of anger, aggression and impulsivity evidently can limit progression from suicidal ideation to acts. Effective suicide prevention requires focused assessment and supervision, especially early in clinical management of patients with major mood disorders, with appropriate pharmacological and psychosocial interventions.