They pitched a big tent on the roof of an office building overlooking the Capitol rotunda the other day for a party to celebrate a new law that treats mental illness and addiction like any other chronic disease. But the tent still wasn't big enough for the man standing almost alone amid the crowd.

"I don't dare tell anyone I am a recovering alcoholic," he whispered to me as if somebody might overhear his revelation in the noisy tent. "It's way too risky."

His boss, an influential member of Congress, doesn't know. Neither do the directors of the federal agencies that leaned on his legislative expertise to steer the bill through to the finish line. The leaders of the nonprofit organizations that championed the cause have no idea. And the lobbyists who pushed it don't know, either.

And that's the way he wants it. "From a policy perspective, I know the parity bill made sense," he said, insisting that I not reveal his name or whom he works for. "Frankly, though, it's my personal battles that convinced me it was the right thing to do for people. It's just not prudent for anyone to know that I am one of those people."

He told me his recovery began after he sought professional help at a treatment facility in the Midwest. But there was no more time for details. Too many people kept interrupting us to thank him for his work. And besides, his boss was being honored at the party. He had to pay attention to what was happening at the podium.

Congressional passage of the Paul Wellstone and Pete Domenici Mental Health Parity and Addiction Equity Act last month expands the tent of private insurance coverage to include equal treatment for illnesses such as depression, alcoholism, post-traumatic stress disorder and anorexia. Although President Bush immediately signed the parity bill into law, it won't fully take effect until the beginning of 2010, when one of the last major obstacles standing in the way of people getting help will finally disappear.

But as I was reminded in my conversation with the man at the party, the legislation does not remove the biggest obstacle. Former first lady Rosalynn Carter talked about a more formidable foe in her opening remarks at the event:

"Stigma is still the primary obstacle preventing Americans with mental illnesses from getting the care they deserve," Carter said. "We have come a long way by securing insurance parity. But until we erase stigma, people will still be reluctant to seek treatment for mental illnesses when they need it, just like they seek help for other major health problems."

She's been fighting stigma since 1991 through the Carter Center's Mental Health Program. And I've been doing the same through Hazelden's Center for Public Advocacy, where I've worked for the past 13 years.

In fact, the man at the party said his willingness to reveal to me a snippet of his own story was prompted by a "call to action" speech I gave a few years ago about ways to reduce stigma. In the speech, I encouraged people who have recovered from addiction or mental illnesses to stand up and speak out in public about their experiences.

Over the years, thousands of people have started doing this, and groups such as the National Alliance for the Mentally Ill and Faces and Voices of Recovery have become potent grass-roots movements of change, achieving success through legislation. It is groups such as these that have made a bigger tent.

But until people such as the man at the party feel comfortable enough to stand up too, the tent won't be big enough.

William C. Moyers is the vice president of external affairs for the Hazelden Foundation and the author of "Broken," a best-selling memoir. The paperback edition was released in August 2007. Please send your questions to William Moyers at [email protected]. To find out more about William Moyers and read his past columns, visit the Creators Syndicate Web page at www.creators.com.