The communique issued at the end of the 75th policy meeting of the Organization of Petroleum Exporting Countries yesterday, indicated that for the oil cartel, which has dictated prices for the past dozen years, it was business as usual. But, in fact, after the brief meeting here this week, OPEC will never be the same.

For what happened here this week, according to analysts and observers, represents an end to OPEC as the powerful cartel governing the cost and availability of world energy and the birth of OPEC as just another world trade association whose prices are governed by the marketplace.

The conference, the communique said, had unanimously reelected Indonesian Minister of Mining and Energy Subroto as president. It also discussed but postponed deciding on demands for a redistribution of production quotas while agreeing on the need to keep OPEC's official overall production ceiling at its current 16 million barrels of oil a day.

But the days when OPEC can make the economies of the western world quake by controlling world oil supplies and dictating prices are over -- at least for the foreseeable future.

"OPEC today stands naked like a faded striptease queen," said one senior Arab oil consultant here who asked that he not be named. "First we let prices go, pulling off layers like a stripper. Now we have let go of production, and that is like dropping our clothes on the stage."

In the light of a world where OPEC's share of the western oil market has shrunk from about 60 percent to 40 percent in five years because of greater non-OPEC production and dropping world demand, OPEC has increasingly found its power and influence clipped.

That much was officially admitted by Subroto in a final press conference.

"We feel we are facing a new period in front of us after 25 years of existence, a new situation," he said. "We must devise a new action program, a new strategy, to deal with it."

That the core of this "new action program" will be the acceptance of a new pricing system for OPEC oil was confirmed by Ahmed Zaki Yamani, the Saudi Arabian oil minister who had long fought to rally his fellow OPEC members into a defense of the official OPEC price for a barrel of oil -- currently $26 -- through a disciplined manipulation of OPEC production.

Yesterday he was forced to admit that Saudi Arabia, the most influential member in OPEC by virtue of its vast reserves and large production capacity, finally had thrown in the towel and accepted the fact that OPEC is no longer able to control its own production, much less dictate a price.

Yamani already had signaled acceptance of this fact in the past couple of months when he signed special contracts with three major world oil companies -- Exxon, Mobil and Texaco -- that had the price of a barrel of oil pegged not to OPEC's official price but to the value in the marketplace of the refined oil products -- gasoline, heating fuel, diesel -- that are derived from crude.

The practice generally has meant that the barrel of oil is sold for anywhere from $3 to $4 less than the OPEC benchmark price that Saudi Arabia had defended so long.

More important was the Saudi decision a month ago to quit trying to limit OPEC production surpluses by shrinking Saudi production while other nations, disregarding the organization's regulations and agreements, consistently produced more than their quotas.

Saudi Arabia, whose production dropped to about 2.4 million barrels a day in August, has decided to increase its production to its full quota of 4.35 million -- a decision that is expected to have a major impact on oil prices by next spring, when winter demand slumps.

Yamani made it clear that it is now up to OPEC and its members to face reality and come up with some new pricing system before spring. Until then, because of growing winter demand and the shortfalls in production of Iranian oil caused by Iraqi bombing of its terminals, Yamani does not expect oil prices to drop appreciably.

Whether such an agreement can be expected is anyone's guess. To date OPEC members have been unable -- or unwilling -- to reach any agreement on new pricing arrangements or production allocations among member nations. The mood has been increasingly one of each for himself.

As Tam David-West, Nigeria's minister of petroleum and energy, put it before leaving Vienna: "Any country is free to do what is consistent with its own national interest. That comes first."

In its members' decision to follow their own national interests -- and individual markets at whatever price they can sell their product -- OPEC has, in fact, lost the two pillars of its power -- pricing and production controls.

Because oil demand in the industrial world will continue and non-OPEC production is expected to peak in the next five years, it is still too early to count OPEC out as an influence in the future. But the consensus here is that its glory days have come to an end.

"What is so bad about that?" asked Subroto. "We have to be realistic. There are changes in the market."