Many years ago, one of my closest friends and I made a pact: If either of us again became dangerously depressed, we would meet at his home on Cape Cod. Once there, the nonsuicidal one would have a week to convince the other not to commit suicide--a week to present all the reasons we could why the other should go back on lithium (we both had a tendency to stop taking our medication); a week to cajole the other into the hospital; a week to invoke conscience; a week to impress upon the other the pain and damage to our families that suicide would inevitably bring. We decided that this should be long enough to argue for life. If it didn't work, at least we would have tried.

Years later--my friend had long since married and I had moved to Washington--I received a telephone call from California. My friend had put a gun to his head and pulled the trigger. He had not called me, nor, I suspect, had he even thought of calling me. No week on Cape Cod; no chance to dissuade.

Although shaken by my friend's suicide, I was not surprised by it. Suicide is not beholden to an evening's promise, nor does it always hearken to plans drawn up in a lucid moment and banked in good intentions.

I know this for an unfortunate fact. Suicide has been a professional interest of mine for more than 20 years and a very personal one for much longer. I have a hard-earned respect for suicide's ability to undermine, overwhelm, outwit, devastate and destroy. As a clinician, researcher and teacher, I have known or consulted on patients who hanged, shot or asphyxiated themselves; jumped to their deaths from stairwells, buildings or overpasses; died from poisons or prescription drugs; or slashed their wrists or cut their throats. Close friends, fellow students from graduate school, colleagues and children of colleagues have done similar or the same. Most were young and suffered from severe mental illness, and all left behind a wake of unimaginable pain and unresolvable guilt.

I have also known suicide in a more private, awful way, and I trace the loss of a fundamental innocence to the day that I first considered suicide as the only solution possible to an unendurable level of mental pain. Until then, I had taken for granted--and loved more than I knew--a temperamental lightness of mood and fabulous expectation of life. I knew death only in the most abstract of senses; I never imagined it would be something to arrange or seek.

I was 17 when, in the midst of my first depression, I became knowledgeable about suicide in something other than an existential, adolescent way. For much of each day during several months of my senior year in high school, I thought about whether, when, where and how to kill myself. I learned to present a face at variance with my mind. I ferreted out the location of two or three nearby tall buildings with open stairwells. I discovered the fastest flows of morning traffic. And I learned how to load my father's gun.

Over the years, my manic depressive illness became much worse, and the reality of dying young from suicide became a dangerous undertow in my dealings with life. When I was 28, after a damaging and psychotic mania followed by a particularly prolonged and violent siege of depression, I took a massive overdose of lithium. I unambivalently wanted to die and nearly did. Death from suicide had become a possibility, if not a probability, in my life.

Because I was, during this time, a young faculty member in a department of academic psychiatry, it was not a very long walk from personal experience to clinical and scientific investigation. I studied everything I could about my disease and read all I could find about the psychological and biological determinants of suicide. I learned as much as I could about the causes of self-inflicted death.

It is a societal illusion that suicide is rare. It is not. Certainly the psychiatric and addictive illnesses most closely tied to suicide are not rare. They are common conditions and, unlike cancer and heart disease, they disproportionately affect and kill the young. In the United States, more teenagers and young adults die from suicide than from cancer, heart disease, AIDS, pneumonia, influenza, birth defects and stroke combined. It is the No. 2 killer of college students. Suicide kills more than 30,000 Americans a year--one person every 17 minutes.

Suicide is a critical public health problem, as repeatedly emphasized by the Centers for Disease Control and Prevention and stressed recently and forcefully by David Satcher in his report "The Surgeon General's Call for Action for Suicide Prevention," which was released in July.

We know a great deal about the risk factors, causes and treatments for the mental illnesses most intimately tied to suicide--depression, manic depression, schizophrenia, borderline and antisocial personality disorders--and we know how precipitously the risk of suicide rises if these illnesses are combined with alcohol or drug abuse. We have learned from studies of families, and of identical and nonidentical twins, that suicide has a genetic component. Each month, the scientific literature provides greater understanding of the biological vulnerabilities in the brain that--when combined with psychological setbacks, unmanageable stress or cumulative despair--make some individuals far more likely than others to take their own lives.

We know, for example, that young males who are depressed, drink, tend to act in impulsive or violent ways and have easy access to firearms are at a greatly increased risk for suicide, and that those who have previously attempted suicide are far more likely than others to kill themselves eventually. (The number of attempted suicides each year is staggering. Last year in the United States, 500,000 people made suicide attempts that were serious enough to warrant care in an emergency room.)

We also know a great deal about the public health, medical and psychological interventions that are most effective in preventing suicide. We have medications that work well, although not ideally, against severe depression and psychosis. Scientists are developing drugs that, in some people, are able to decrease cocaine and alcohol craving. And we have medications that allay severe anxiety, dampen impulsiveness and mitigate the violent mood swings of manic depression. Clinicians are increasingly aware of the need to identify and aggressively treat suicidal patients with medication, psychotherapy or a combination of both. Most suicides, although by no means all, can be prevented. The breach between what we know and what we do is lethal. And the gap is frighteningly wide between the public's only slight awareness of suicide as a major public health problem and the reality of its terrible death toll.

I became more impatient as a result of writing my recent book about suicide and am more acutely aware of the problems that stand in the way of denting the death count. I cannot rid my mind of the desolation, confusion and guilt that I have seen in parents, children, friends and colleagues of those who kill themselves. Nor can I shut out the images of autopsy photographs of 12-year-old children, or the prom photographs of adolescents who within a year will put a pistol in their mouths or jump from the top floor of a university dormitory. Looking at suicide--the sheer numbers, the pain leading up to it and the suffering left behind--is harrowing. For every moment of exuberance in the scientific advances, or the progress in clinical practice, there is a matching and terrible reality of the deaths themselves: young deaths, violent deaths, unnecessary deaths.

Like many of my colleagues who study suicide, I have seen time and again both the promises and the limitations of our science. I have been privileged to see how good some doctors are and I have been appalled by the callousness and incompetence of others. Mostly, however, I have been struck by how little value our society puts on saving the lives of those who are in such despair as to want to end them.

Kay Redfield Jamison is professor of psychiatry at the Johns Hopkins University School of Medicine. This article is adapted from her new book, "Night Falls Fast: Understanding Suicide" (Knopf).

By the Numbers

* Although more women attempt suicide then men in the United States, men are at least four times more likely to die from suicide.

* The U.S. suicide rate has declined for the past two decades from 12.1 per 100,000 in 1976 to 11.4 per 100,000 in 1997, but the rate among young people ages 15-19 has increased by 14 percent, and the rate among children ages 10-14 has increased by 100 percent.

* Between 1980 and 1996, the rate of suicide among young black men ages 15-19 increased by 105 percent.

* Suicide rates are highest among white American males ages 65 and older. Each year, more than 6,300 older Americans take their own lives.

* States with the highest suicide rates: Nevada (24.5 per 100,000), Alaska (21) and Montana (20.8). The lowest suicide rate: New Jersey (7.3). The District of Columbia's rate is 6.6.

* Based on more than 752,000 suicides from 1972-1997, it is estimated that the number of suicide attempt survivors in the United States is 4.51 million.

Sources: "The Surgeon General's Call to Action to Prevent Suicide" (1999); American Association of Suicidology (1997 data)

In College, at Risk

It is because young adults are particularly vulnerable to mental illness and suicide during the college years that psychologist Kay Redfield Jamison urges parents to talk with their college-age children about their family's mental health histories and educate them about symptoms and treatment.

In her new book, Jamison says the first episodes of depressive illness or schizophrenia are most likely to occur while college students are away from home for the first time and subject to new stresses; they may use alcohol or drugs more heavily, and their sleep patterns may be radically altered, which can trigger a psychotic episode.

She also encourages parents who accompany their children at college check-in time to explore the student health facilities in addition to the usual tour of libraries and residence halls. It helps to find out how the health center deals with students who have mental illness, since counseling and psychiatric services vary in quality from campus to campus.

At Harvard University, for example, a group of students has set up a mental health awareness program on campus that helped to establish a professor from the psychiatric department as its adviser, sponsors lectures, maintains a Web site and runs a support group for students.

CAPTION: Major Causes of Death Worldwide (This graphic was not available)