WASHINGTON -- Securities and Exchange Commissioner J. Carter Beese Jr. said yesterday that he plans to leave the agency later this year.

Mr. Beese, who worked previously with Alex. Brown & Sons, said he was resigning for personal reasons, and he didn't say what he plans to do in the future.

"After spending vacation time with my wife and three small children over the past few weeks, I have decided to return to private life," Mr. Beese said.

Because he lives north of Baltimore, Mr. Beese had to commute three hours each day to get to work at the SEC.

Mr. Beese, who was appointed by President Bush and has worked at the agency since March 1992, is the only Republican member of the five-member commission. No more than three commission members can be from the same political party. SEC Commissioner Mary Schapiro, who has been nominated to be chairwoman of the Commodity Futures Trading Commission, is a political independent.

At the commission, Mr. Beese was known as an advocate of free markets. He often noted that imposing additional regulation on securities trading in the U.S. provides incentives for more transactions to be done offshore.

He warned about the potential dangers of the misuse of derivatives, instruments whose value is based on an underlying asset or index, although he didn't call for legislation governing their use and supervision. "The problem posed by derivatives is not with the products themselves, but with how end-users are using them," he said in a speech earlier this year.

Mr. Beese also called for making the U.S. regulatory system more cost-effective in response to increased flows of capital across national boundaries, and was active in encouraging individuals to save for retirement. He highlighted the need for easily understood disclosures for mutual funds, individual retirement accounts and 401(k) plans.

As a former partner at the investment banking firm Alex. Brown & Sons in Baltimore, he brought to the commission a first-hand knowledge of trading and markets. The three others commissioners, in contrast, have backgrounds primarily in securities law or government. SEC Chairman Arthur Levitt, however, has 16 years of experience on Wall Street.