I hope nobody who's rational expected the OPEC ministers to lower production quotas at their meeting in Vienna last week. Crude prices are doing a stellar job of rising up on their own, having essentially doubled in a matter of months, something to which investing Fools should be paying extremely close attention.

Following a pair of significant cuts in the second half of 2008, the 12-member cartel determined that it was best to leave well enough alone for the time being and stick with the current nation-by-nation allotments. Clearly the members are weighing the advantages of higher prices against the effects those prices would have on a still fragile global economy.

OPEC, whose members produce roughly 40% of the global oil supply, could make a difference there, at least in the short term. Its current production target has the organization producing at about 10 times ExxonMobil's (NYSE:XOM) daily output.

Easily the biggest problem with shrinking quotas within the cartel is that of enforcement. For instance, it appears that the 11 members at least theoretically bound by quotas -- Iraq isn't -- raised their production by 130,000 barrels a day in April. I'm betting that a slug of the cheating is occurring in Iran, which reportedly needs $70 (or more) oil to balance its budget.

Antics like those occurring in Nigeria and Venezuela are serving as de facto production cuts. As I recently told you, pipeline attacks in Nigeria have caused a 100,000-barrels-per-day shut-in there by Chevron (NYSE:CVX). Subsequently, there have been reports that the militants have attempted to attack a 125,000-barrels-per-day offshore production platform operated by Total (NYSE:TOT).

And then there's Venezuela, where Uncle Hugo has ceased paying all but the largest oilfield service firms, has forcibly assumed the operation of an Ensco (NYSE:ESV) rig, and confiscated Williams Cos.' (NYSE:WMB) equipment. Recently, state-run oil company PdVSA assumed control of 11 Tidewater (NYSE:TDW) vessels and a shore base operating in the Lake Maracaibo region.

So OPEC is far more complex than just a group of producing nations that convene regularly for quota setting. Indeed, with the shenanigans in a couple of its member countries, a formal production cut may have been unnecessary. At the same time, my contention is that crude will continue to higher levels. Absence of a formal declaration simply provides Fools more time to up their ante in this recovering sector.  

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Fool contributor David Lee Smith doesn't own shares in any of the companies mentioned. He does, however, welcome your comment or questions. The Motley Fool has a world-recognized disclosure policy.