In its most dramatic organizational overhaul in decades, the FBI is changing its structure to address internal problems with the handling of information and put a greater emphasis on preventing terrorism and espionage, rather than simply responding to such crimes after they happen.

In an interview, FBI Deputy Director Robert M. Bryant characterized the restructuring, which bureau officials plan to announce today, as a "sea change" that will encourage the sharing of information between divisions and better communication between analysts and senior officials.

"We collect a lot of information, but . . . our predictive intelligence is poor," said Bryant, the second-in-command at the bureau. "The bottom line is, 'We don't know what we know.' "

The reorganization is an integral part of a broader transformation of the FBI under Director Louis J. Freeh and reflects his commitment to the bureau's growing role in fighting terrorism in the United States and around the world. The FBI's counter-terrorism budget has more than tripled in the past three years, while its overall budget has doubled from $1.5 billion to about $3 billion since Freeh took the helm in 1993.

Under the restructuring, the number of major operating divisions at the bureau will increase from two--the Criminal Division and National Security Division--to four. A new Counterterrorism Division will focus on terrorist threats and include the bureau's National Infrastructure Protection Center and its computer crimes unit; an Investigative Services Division will consolidate analysts who had worked in separate divisions and will also include the bureau's hostage rescue team and negotiators.

Bryant said the old system left analysts in different divisions focused too narrowly on their areas of expertise. For example, a suspect could be investigated separately for being a possible spy, terrorist or criminal, and information gathered about that person by various FBI specialists would not necessarily be shared. Bryant said such failures to share intelligence between divisions had resulted in senior FBI officials not always being aware of critical information in cases under investigation, including recent probes into campaign finance and Chinese espionage.

Bryant said the goal is to bring about a fundamental change in the bureau by transforming the FBI from a law enforcement agency with a structure and culture that revolved mostly around investigating crimes after the fact to one that puts more emphasis on identifying threats and preventing crimes from occurring.

"The FBI for the next century has to not only be able to react to a bombing in Oklahoma City and put a thousand agents on it [but] to be able to prevent that," said Bryant, who has worked at the FBI for 31 years and is leaving at the end of the month to take a job in the insurance industry fighting fraud. "It is very easy to revel in our glory where we solve crimes that happened. I think our greater obligation is to prevent them."

Bryant's assessment of the difficulties inside the FBI is unusual for a senior official of the bureau, which is better known for trumpeting its achievements. And it comes as senior FBI officials are actively implementing the first stages of the sweeping reorganization, following the plan's recent quiet approval by Congress.

Bryant, himself a former head of the national security division, said one problem with the existing structure is that the national security chief frequently becomes preoccupied by serious terrorist threats, leaving no senior official to pay sufficient attention to counterintelligence. The creation of a new, separate anti-terrorism unit will permit the head of the National Security Division to focus heavily on counterintelligence. This change will enable the FBI, Bryant said, to adopt a more aggressive posture on espionage threats and other foreign intelligence matters where the FBI works closely with the CIA and the Department of Defense.

Despite the need for changes, Bryant said the FBI does a solid job of investigating and solving the vast array of crimes. He said the new design for the FBI followed vigorous debate within the bureau and is linked directly to a new five-year FBI strategic plan that creates three tiers of priorities for the bureau, with the greatest emphasis on a group of "Tier One" programs: foreign intelligence, and combating terrorist and criminal activities that affect national and economic security.

In the short run, Bryant said the new structure will not require additional funding for the FBI. But the deputy director said additional funding would be needed in the years ahead to help the FBI catch up with fast-moving changes in technology.

Bryant said the FBI's aggressive efforts to develop better predictive and anti-terrorism capabilities would raise some concerns about civil liberties issues. But he said the bureau can accomplish its new mission while holding fast to traditional standards of gathering intelligence that respect the public's right to privacy and the need to handle classified information properly.

"We are going to carefully adhere to the guidelines and the rules of the road," Bryant said. "It is just basically making sure that we are getting the most out of the information we have."

Bryant called the structural changes the FBI is making "overdue" and said the bureau has moved too slowly on some matters in the past, primarily because of its structure and the way it handled information.

"The violent crime issue in this country, in my opinion, got way out ahead of us," Bryant said. "When we finally did mobilize, I think we were very effective. But I think if we basically had been doing more predictive intelligence, we would have moved resources much faster."

CAPTION: Deputy FBI Director Robert M. Bryant describes the restructuring as a "sea change" that will encourage internal sharing of information.