What is OPEC and how does it actually work?

If you read any oil-market coverage, the words “OPEC” and “OPEC+” appear constantly, usually without explanation. The mechanics actually matter — the difference between “OPEC announced a cut” and “OPEC actually cut” determines whether oil prices move 2% or 10%.

What OPEC is

The Organization of the Petroleum Exporting Countries was founded in 1960 by Saudi Arabia, Iran, Iraq, Kuwait, and Venezuela — five oil producers tired of the seven major Western oil companies setting their prices. The founding members wanted price control of their own resources. Sixty-five years later, that’s still the mission.

Today’s membership is 13 countries, dominated by Saudi Arabia, with Iraq, the UAE, Kuwait, and Iran rounding out the consequential bloc. African members (Algeria, Libya, Nigeria, Equatorial Guinea, Gabon, Republic of Congo) and Venezuela contribute smaller volumes. Members rotate in and out — Indonesia and Qatar both left, Ecuador rejoined and left twice. The group represents about 30% of global oil production.

The mechanics: quotas and cheating

OPEC operates on a quota system. The group meets (usually twice a year, more often during turbulent periods), agrees on a total production target, and divides that target among members. Each country agrees to produce no more than its assigned share.

The challenge: every member has a strong incentive to cheat. If quotas are respected and the group hits its target, oil prices rise. Each individual member can earn more by quietly producing above their quota and selling at the higher prices the group is creating. This creates a classic prisoner’s-dilemma dynamic where collective restraint is hard to sustain.

Enforcement is largely a function of Saudi Arabia. The kingdom has the largest spare capacity, can quickly flood the market to discipline cheaters (driving prices below break-even for high-cost producers), and has done so multiple times — most dramatically in 1986 and again in 2014-2016. The credible threat of Saudi punishment is what makes the cartel function.

OPEC+ — what changed in 2016

In late 2016, OPEC made a strategic move that fundamentally changed its market power. Russia and 9 other non-OPEC oil producers (Mexico, Kazakhstan, Azerbaijan, and others) joined a coordinated production agreement. The expanded group — “OPEC+” — represents about 40% of global production, enough to meaningfully move prices.

The driver was the 2014-2016 oil-price collapse. Saudi Arabia and Russia both decided that competing for market share was destroying everyone’s revenue. Coordinating beat competing. The 2016 deal cut a combined 1.8 million barrels per day and stabilized prices.

OPEC+ has held since, with periodic strain. The 2020 COVID demand collapse triggered the largest production cut in history. The 2022 Russia-Ukraine war created tension between Saudi and Western interests. Each crisis has tested the alliance, and each time it has held.

How OPEC actually moves the market

OPEC announcements move oil futures within seconds. The actual production effect lags 30-90 days as producers adjust output, ships are loaded, and inventory works through the system.

Three indicators matter more than the announcement:

1. The press-conference language. A “we will respond appropriately to market conditions” message from the Saudi energy minister is far more pointed than it reads. The market is reading nuance.
2. The next monthly production data. Whether members actually produce at their quotas (as reported by independent secondary sources, not member self-reporting) tells you if the deal is real.
3. The OPEC+ JMMC meeting outcomes. The Joint Ministerial Monitoring Committee meets monthly. Its statements adjust quotas in response to market conditions. These adjustments are where the real action is.

Saudi Arabia’s outsized role

The kingdom’s spare capacity — typically 2-3 million barrels per day that can come online within 90 days — gives it the only tool that can credibly threaten cheating. No other member has the same lever.

This is why OPEC decisions are functionally Saudi decisions. The other members can lobby, hedge, or quietly cheat, but the actual production target is whatever Riyadh agrees to enforce.

What to watch in any cycle

For any oil-impacting event, the OPEC question is always: will Saudi Arabia bring spare capacity online to offset disruption?

If yes, oil spikes are short. If no, oil spikes hold. Saudi production guidance — communicated through MoMR reports and OPEC+ press conferences — is one of the most-watched indicators in global markets for exactly this reason.

For more on Saudi posture specifically, see our Saudi diplomatic posture analysis. For how oil moves through cycles, see the markets playbook.