WASHINGTON --- With Bernard Madoff on his way to jail, attention is shifting to the next fraud -- and to the agency responsible for preventing it.

The Securities and Exchange Commission lost credibility when it emerged that a tipster had been trying to blow the whistle on Mr. Madoff for years but had been brushed off repeatedly. Since Mr. Madoff's case came to light, the agency has announced a series of changes it hopes will improve enforcement, making it easier to detect and root out fraud before it approaches this massive scale.

But obstacles remain, including the finding in a recent oversight report that agency lawyers lack necessary support staff and resources. And even with the benefit of hindsight, experts say, eliminating fraud is about as likely as eliminating greed.

Here are some questions and answers about what the SEC is doing to shore up its examination and enforcement actions.

Q: Could a Madoff-style fraud happen again?

A: Of course. Enforcement is by definition a backward-looking process, with officials exposing and punishing wrongdoing only after it's been committed. As far as the SEC knows, there are more Madoffs starting up right now.

But officials say fraud on Mr. Madoff's scale is unlikely because he was an uncommonly talented crook, quietly gaining the trust of investors, regulators and power brokers over decades.

Q: What are they doing to stop the next Bernard Madoff?

A: The examinations division, which is responsible for day-to-day oversight, will be improving examiners' expertise in fraud detection and in complex financial products, looking more closely at firms deemed more likely to commit fraud and improving handling of tips and complaints. That's according to a speech this month by Lori Richards, who directs the SEC's Office of Inspections and Examinations.

SEC Chairman Mary Schapiro has installed a new director of the Division of Enforcement: Robert Khuzami, a former federal prosecutor. He has launched efforts to improve the SEC's enforcement capabilities, including streamlining processes, and advocates pouring vast resources into hiring.

The agency also will introduce a new computer system intended to track and sift through the complaints that come in, which number between 750,000 and 1.5 million a year.

Q: Aren't there some concrete loopholes the SEC needs to close?

A: Mr. Madoff exploited the opportunity to act as both investment adviser and custodian of his clients' assets. That meant there was no one to verify whether the assets existed, or whether he was making the trades he claimed.

The SEC proposed a new rule that would require third-party verification of the assets.

But closing loopholes doesn't prevent abuses, warns Laura Unger, a former commissioner and acting chairwoman of the SEC.

"Disclosure and rules are always changed after the crisis," she says. "You're hard-pressed to prevent the next thing before it happens because it's always going to be something different."

Q: How can we be sure the SEC even understands where the problems were?

A: In August, SEC Inspector General David Kotz is expected to release a long-awaited investigation of the breakdowns that allowed Mr. Madoff to pull off his scam undetected. It will examine information sharing between the examination and enforcement divisions, and attempt to explain why a tipster on Mr. Madoff's fraud was unable to attract the agency's attention for more than a decade.