FORT LAUDERDALE, Fla. — Memo to Joe the Plumber: There's work to be done on Wall Street.

The plumbing of the financial system, the day-to-day trading in short-term credit markets, doesn't work well. That has the money market mutual fund industry on edge.

These funds, perceived as substitutes for cash and nearly as safe as federally insured bank accounts, have been through a harrowing September and October.

It started with a money market mutual fund announcing that it was halting withdrawals and could not completely return investors' funds. Then came more than a $200 billion run on fund assets, as people rushed to get their money out of what suddenly appeared to be an unsafe corner of the market

Things are beginning to settle down, industry analyst say.

"It looks as if it's still a delicate situation, but the money markets in general have been recuperating," said Peter Crane, president of Crane Data, a money-market research firm.

Crane says at least 20 parent companies of money-market funds have pumped billions of dollars of cash into their funds. They had to after the subprime crisis began to explode, because almost overnight, money market funds couldn't sell securities tied to such troubled investment banks as Lehman Brothers and to risky mortgages.

Without government assistance, the money-fund industry leaped into the crisis with private rescues, with loads of discussion on Web sites about the safety and underlying investments of fund and even by bailing each other out, as Federated Investors recently did for a Putname Investments fund.

Fidelity Investments, the behemoth that manages $440 billion in money market funds, now discloses the holdings of its funds daily to any customer who asks.

And, the U.S. Treasury last month set up a temporary insurance program that most major funds have joined to guarantees investors' funds. That's brought a lot of calm to the sector.

With insurance, and now with the government's attention to the economic crisis, consumers "shouldn't have any concerns," said Deborah Cunningham, who is in charge of money markets at Federated, which has $271 billion in money market funds.

The Federal Reserve has been trying to try to unclog the credit markets, where money market funds do the job of buying and selling very short term securities.

So is that it? Are money funds safe?

"The consumer doesn't really have much to worry about," says Morningstar Fixed Income Investment Analyst Eric Jacobson.

The market, though, remains unsettled. Investors still aren't certain where all the risks are in the debt markets. And the question, Jacobson says, is "are the institutions and normal players willing and able to step up and buy and sell in the normal way they have for years?"