Mayor Gavin Newsom said Monday that he plans to seek counseling for alcohol use, following the disclosure that he had an affair with the wife of a trusted aide.

Newsom, 39, said that while "my problems with alcohol are not an excuse for my personal lapses in judgment," he had stopped drinking and wanted professional help staying sober.

"Upon reflection with friends and family this weekend, I have come to the conclusion that I will be a better person without alcohol in my life," Newsom said in a statement.

Newsom said he would be receiving treatment from Mimi Silbert, the founder and director of the Delancey Street Foundation in San Francisco and that it would not affect his duties as mayor.

Delancey Street provides a residential program for hard-core addicts, including ex-convicts and prostitutes. Although the mayor plans to work with her on an outpatient basis, the program she has in mind for him will hardly be cushy, said Silbert, who met with Newsom over the weekend.

"The good thing, to me, is that he came and asked for help from a place he knows would not be light," Silbert said.

Delancey Street, which she founded in 1971, does not rely on the 12-step philosophy of Alcoholics Anonymous, but works to address the underlying reasons for excessive drinking, she said.

For privacy reasons, Silbert would not elaborate on how specifically she planned to help Newsom, whom she described as "very serious" about getting help.

Before taking office in 2004, Newsom founded a wine store, a string of highly successful restaurants and the Plump Jack Winery in Napa County. He is running for a second term in November.