Now that President Obama has unveiled the United We Serve campaign to encourage Americans to volunteer this summer, some nonprofit groups that already work with volunteers are wondering if they have to create something new.

“The answer is no,” Nicola Goren, acting chief executive of the Corporation for National and Community Service, told participants in the National Conference on Volunteering and Service. “You just have to keep doing what you’re doing.”

But, she said, groups can promote the campaign in various ways — by posting a link to the administration’s volunteer Web site, Serve.gov on their own sites; issuing a press release about their participation in the campaign; sending a message to their e-mail distribution lists; and posting stories about how their volunteers are making a difference on Serve.gov.

Ms. Goren also urged groups to think of ways to increase opportunities for people to volunteer with their programs and “collaborate in new and different ways to expand your reach.”