For Earle Palmer Brown, the gateway to the West is San Diego.

In a move to establish a national presence, the Bethesda-based advertising agency Earle Palmer Brown -- the largest in the Washington area -- has tentatively agreed to acquire Franklin & Associates Advertising and Public Relations of San Diego.

Three years ago, EPB was a local firm with a single office and about $100 million in annual billings. But through a series of acquisitions, most in 1987 and 1988, the agency has become one of the larger East Coast advertising firms, with seven offices from New York to Florida and annual billings of more than $300 million. The original Bethesda office now accounts for about $150 million of the company's total billings.

But its management wanted to "build a national firm both in prominence and presence," said Jeb Brown, chief executive of the agency and son of its founder and namesake. A West Coast presence, he said, would not only give the agency a better understanding of the market, but also a chance "to be a participant in one of the strongest {economic} regions in the country."

Attracting more clients probably will be high on Earle Palmer Brown's list of priorities in the coming months as at least one of its best-known accounts, for which it produced a series of critically acclaimed ads, soon will leave its ranks.

Roy Rogers Restaurants, which Marriott Corp. sold to Hardee's Food Systems Inc. in April, has been one of the agency's biggest accounts, at it's peak bringing the agency $15 million in billings. As the Roy Rogers franchises are gradually turned into Hardee's restaurants, EPB's role will dwindle.

Another major account also may be in jeopardy. Bob's Big Boy restaurants, also a Marriott subsidiary, is up for sale, although it has not yet been sold. At the International Advertising Film Festival in Cannes in June, EPB was one of five U.S. agencies that received a Gold Lion award -- for a Bob's Big Boy television ad.

The agency also represents USAir, BellSouth, Omni Hotels, the American Floral Marketing Council and Blue Cross and Blue Shield's Federal Employees Program.

"As we get larger, we are going to attract larger clients who are more interested in larger programs," Brown said. A West Coast office "was significant in being able to attract national clients, and attract clients that are based only on the West Coast."

The San Diego agency, with annual billings of about $35 million, does not have clients in the same areas as other EPB agencies, Brown said. Most of its clients are regional, such as the San Diego Zoo, the San Diego Padres and the Union/Tribune Publishing Co.

Franklin found the EPB deal attractive because it, too, wanted to enter national arenas, Brown said. "It was just a matter of timing," he said. "{Franklin was} owned by Great American Bank, and they had to divest some of their assets."

Its location also attracted the Bethesda agency, Brown said, despite San Diego's relative anonymity as an advertising center.

"The possibility of being the leading agency in San Diego rather than an also-ran in Los Angeles interested us," he said. "San Diego is a good market. It's livable, it's got a good, steady economic base. We felt like that would be a good place to start rather than to jump into the middle of the jungle in L.A."

Sources said last week, however, that EPB is discussing similar options with a Los Angeles firm.

Earle Palmer Brown would not disclose details of the Franklin deal. Acquisitions in the advertising field can be structured in many different ways, from a simple business alliance with options to buy at a later date -- a set-up that requires very little up-front money -- to buying the firm outright.

Whatever the terms of this deal, it has not left Earle Palmer Brown strapped for cash, Brown said. He said the agency is considering other West Coast acquisitions, although he did not elaborate.