When T. Gary Rogers and W.F. Cronk bought Dreyer’s Grand Ice Cream for $500,000 in 1977, they didn’t exactly know what the future would bring.

“When we bought this little company, it was doing $6 million in sales,” recalls Rogers, who’s retiring as CEO at the end of the year. “We didn’t have an explicit mission, but if we did, maybe it was to someday expand the reach of Dreyer’s throughout the West. Our goal was to be the leading Western ice cream manufacturer.”

Though at the time Dreyer’s did little business outside the San Francisco Bay area, Rogers says becoming best in the West wasn’t as daunting as it sounds. The ice cream industry then was composed of many regional milk processors that made ice cream as an incremental business.

So by 1981, Dreyer’s reached that first goal, and the company went public with a value of $45 million.

The next goal was to become the leader in the national market, of which Dreyer’s had about a 4 percent share. Breyers, the national leader at the time with dominance on the East Coast, had about 10 percent.

So through steady expansion, and launching Grand Light along the way, Dreyer’s passed Breyers in 1994. The new Dreyer’s goal, Rogers says, was then to become the “pre-eminent” ice cream company in the country, encompassing all formats.

That battle continues. In 1994, Kraft Foods sold Breyers to Unilever, which “has proved a much tougher competitor,” Rogers says. “It’s been a real dogfight.”

Dreyer’s and Unilever each have about 25 percent market share, Rogers says. “The industry over the last 30 years has gone from a regional industry into one that’s becoming an oligopoly,” he says. “Both of us have come from almost no share 30 years ago.”

Rogers envisions the future of the ice cream industry like the beverage industry with Coke and Pepsi — two major companies dominating the national market, surrounded by niche players. “The charge now is to complete the mission,” he says. “Current momentum suggests it’s in the cards.”

But Rogers will be content to watch that happen from the sidelines. “I’ve been here for 30 years and it wouldn’t be fair to the successor team to have my shadow on this company,” he says. “It’s time to let the new team find their way.”

Rogers, who returned from an overseas vacation shortly before this interview, will keep busy with his position as deputy chairman of the San Francisco Federal Reserve Bank, as well as other projects he’s not yet at liberty to divulge.

“I have great joy and pride,” he says, “in having been a steward of this company for 30 years.”