The good news on the subject of Ad Age's editorial, "Why PSA Causes Falter," is that so many of them don't falter.

Public service advertising campaigns have been successful in periods of both calm and turmoil for many years. The Advertising Council has much evidence to support the fact that "steady commitment to a powerful campaign pays off."

Sure, the message gains extra impact and the media run the messages more frequently for a while when the issue is of current concern, like the Centers for Disease Control campaign against AIDS.

But the mission of public service advertising is not to be talked about. It is to be acted upon. In fact, much of the argument over a campaign like the CDC's by people it doesn't target dilutes the power of its call to action by people it's designed to help.

The triumphs of public service advertising have been achieved gradually, over time. With few exceptions, in our experience, the issues that PSAs address are not short term. Those short-term exceptions: specific disaster relief or the kind of campaign that took Drs. Salk and Sabin's achievements to the public and helped conquer polio. But even here, another disaster or disease is bound to surface.

In its editorial, Ad Age rues, "Too bad we in the media haven't figured out ways to help fight more than one war at a time."

Well, you have. It's just that some of them are less salient and less glamorous than other battles that are on the front page or the nightly news shows for three days, only to be replaced by another hot news story.

The United Negro College Fund is only rarely on the front page of the newspaper. The 20-year increase of more than 800% in fund-raising came from ongoing, day in, day out organized fund-raising efforts with great advertising leading the way. Some years the advertising was better than others. Some years the media gave a lot of donated space and time, other years less; many ads run in less than perfect dayparts or less than perfect adjacencies. But give them time, frequency and consistency and they will work.

No other groups rival in power and resources the forces of advertising and media to affect actions against social ills. And what is being achieved-while not enough-is still astonishing. It's not a matter of hitting hard on one disease or the evils of violence, ignorance and prejudice and then moving on to the next emergency. Social problems aren't special events.

We used to think differently. When the Ad Council got going on peacetime issues back in the 1950s, its leaders organized procedures to manage what they called the "Sunset Effect." That was based on the theory that a blitz of advertising could be expected to make a problem go away pretty quickly. So the proviso was that no campaign issue could be addressed for more than three years, with only a rarely-to-be-granted exception. After three years the first wave of six campaigns came up for review. Only one, on relief of a temporary famine in the Balkans, failed to be renewed.

The advertising community has a realistic appreciation for the magic its creative minds and media muscle can achieve when applied to social problems.

But it isn't quick. It isn't easy. James Webb Young, who first articulated the Ad Council idea back in 1941, later said he'd become convinced that "it takes more cunning to do good than to do evil."

PSAs falter for a number of reasons: lack of impact, relevance, courage or clarity, from wallowing in the problem rather than steering the public toward a solution and, of course, too little media. Many falter because they address situations where advertising and the individual choices it affects can't make much difference.

When focused, sharp, lively and applied for the long pull, PSAs have power beyond expectations to make a measurable difference in life -- with or without crisis and clamor.

Ruth Wooden is the former president of The Advertising Council.