Rob Shepardson and Lenny Stern enjoyed working together on an election campaign in Pennsylvania. So they decided to put their talents for organization to work on behalf of corporations.

Their collaboration, called SS+K for Shepardson, Stern, and their friend Mark Kaminsky, was launched 13 years ago and is a business version of the political campaign. But it’s on behalf of clients as varied as the New York Knickerbockers, Polo Ralph Lauren, Unicef and the Bill & Melinda Gates Foundation.

SS+K describes itself as a “communications firm” that uses advertising, public relations or other skills to win favorable public opinion for its customers.

“We all started on political campaigns and these are simply a bunch of people in a room, with different backgrounds, who know they need to move the needle quickly in order to win,” said Mr. Stern in a recent interview in SS+K’s offices overlooking Wall Street.

The firm consists of 100 self-described “refugees” from ad agencies, political campaigns, public relations firms, graphic design houses and journalism. On top of that, SS+K embraces another element: its exclusive, cross-ownership arrangement with Creative Artists Agency (CAA), Hollywood’s top talent agency.

“CAA started off as a client then we became partners,” said Mr. Stern.

SS+K is partly owned by CAA, and owns part of CAA in return. This arrangement gives it a seat at the table with CAA’s 260 agents when they are talking about their writers, directors, or performers.

“We know what the hopes and dreams of Nicole Kidman are and her movie projects two years ahead of time,” he said. “So if a client wants to reach out to women and we can tell them that there are 20 or 30 pilots in the works about empowered women, they know where they want to be.”

SS+K’s unusual and multi-disciplined approach is illustrated by recent campaigns for the Lance Armstrong Foundation, retailer Abercrombie & Fitch, Vans Shoes for teenagers and the New York Knicks.

A few years ago, Mr. Armstrong, the Tour de France champion and cancer survivor, asked SS+K to help him get publicity for his foundation’s two annual fund-raising events.

“He wanted fund-raising but we thought, looking forward, about creating a movement [for his cancer-fighting cause] and to build it around Lance,” said Mr. Stern. “We created ‘Livestrong,’ built a website and launched a yellow bracelet as a symbol. Eventually, 60 million bracelets were sold, raising $60 million for his foundation.”

The campaign gained speed through SS+K’s Hollywood connection and celebrities such as Robin Williams and Oprah Winfrey began donning the bracelets in support of Lance Armstrong’s foundation.

Today, the foundation hosts its site on behalf of cancer survivors and others so they can share their stories and insights.

The Hollywood connection also played a role in a campaign which began with an assignment from some music executives.

“CAA clients, which included certain musicians and music execs involved in alternative music, wanted us to help them reach angry 16-year-olds. So we created the ‘Warped Tour’ concert series in various cities which combined extreme sports and alternative music,” SS+K’s chief creative director, Marty Cooke, said.

Music promotion was also brought into play by SS+K on behalf of Abercrombie & Fitch in new stores they were launching for teenagers in suburban malls. Spaces were set aside in these retail outlets. They were dubbed Lounge 22 and were places where kids could get soft drinks and a seat to watch mini-concerts involving new rock bands.

“This drove traffic into the stores and launched some bands into greater popularity,” Mr. Stern said.

For the New York Knicks, the firm orchestrated a more traditional advertising campaign to generate ticket sales. Humorous scenes were filmed involving director Spike Lee, tennis great John McEnroe and other fans talking to life-size cardboard cutouts of the players.

Cutouts were then attached to street-level billboards. When some were stolen, local newspapers picked up the story.

Most recently, SS+K played a purely public relations role when it handled the logistics and publicity surrounding the announcement by the Gates Foundation of Warren Buffet’s multibillion-dollar gift.

Such nonprofit clients are mostly the bailiwick of Mr. Shepardson, a graduate of the John F. Kennedy School of Government and consultant on political campaigns in Latin America and Central Europe.

“We love the work and love making a difference too. That’s part of our DNA,” he said.