After negotiating for the better part of a decade, 12 Pacific Rim nations have finally come to an agreement about how they should conduct trade among one another. Until now, the drafts had been under wraps, available only to lawmakers, staff with clearance and advisers. Today, the parties released the full text. We're still reading to see what's in it, but environmentalists, labor unions and humanitarian groups are already decrying the agreement as a repeat of past trade agreements, while U.S. industry groups — primarily agriculture, pharmaceutical makers and retail companes — have supported it.

Over the past few months, we've covered the battle over fast track legislation, the treatment of tobacco under the text, the concerns around labor rights, the challenges of negotiating in secret, a dustup over human trafficking and the importance of enforcement. We'll write more as we figure out what's in the deal. In the meantime, if you're just getting caught up, here's a place to start.

1. What is the Trans-Pacific Partnership? 

Basically, it's a giant free-trade deal between the United States, Canada and 10 countries in the Asia-Pacific region that was under negotiation for nearly a decade (it began as an agreement between Singapore, Chile, New Zealand and Brunei before the United States took the lead in 2009). It eliminates tariffs on goods and services, tears down a host of non-tariff barriers and aims to harmonize all sorts of regulations when it's ratified.

2. Giant, huh? How giant? 

The countries that are party to the agreement — including Australia, Brunei, Chile, Malaysia, Mexico, New Zealand, Canada, Peru, Singapore, Vietnam, most critically Japan (and, potentially, South Korea) — are some of the United States' biggest and fastest-growing commercial partners, accounting for $1.5 trillion worth of trade in goods in 2012 and $242 billion worth of services in 2011. They are responsible for 40 percent of the world's GDP and 26 percent of the world's trade. That makes it roughly the same size as the Trans-Atlantic Trade and Investment Partnership, another huge trade agreement that got rolling this past summer. The hope is that more countries in the region will join down the line.

3. So the big country not in the TPP is ...

That's right: China. The Obama administration's focus on the TPP is part of its "pivot" to Asia — then-national security adviser Tom Donilon called it the "centerpiece of our economic rebalancing" and a "platform for regional economic integration" — after too many years of U.S. foreign policy being bogged down in the Middle East. Scholars such as Columbia University's Jagdish Bhagwati are worried that the TPP goes further, as an effort to contain China and provide an economic counterweight to it in the region. Many of the TPP's current provisions are designed to exclude China, such as those requiring yarn in clothing to come from countries party to the agreement, and could invite retaliation. In addition, 60 senators have asked for the final agreement to address currency manipulation, which wouldn't directly affect China as a nonmember but could create a framework for broader action. The White House consistently declined to make that a priority, saying there are better ways to prevent countries from manipulating their currencies to make their goods cheaper.

4. I thought we already had a World Trade Organization. Why do we need a separate Asia trade deal? 

The TPP process itself is an admission that the consensus-driven WTO is too cumbersome a venue for "high-standard" trade deals. The WTO's weakness seemed even more apparent in its recent "breakthrough" on customs streamlining, which was all negotiators could salvage from the much more ambitious Doha, Qatar, round, which otherwise has been a failure. Of course, some fear that another regional pact will just add complexity and undermine existing institutions.

5. How is it different from other trade deals we have done? 

Trade agreements used to deal mostly just with goods: You can import X number of widgets at Y price, as long as we know that certain environmental and labor standards are met. Modern trade agreements — including the Trans-Atlantic deal and the TPP — encompass a broad range of regulatory and legal issues, making them a much more central part of foreign policy and even domestic lawmaking.

6. Wait, so how much does this thing actually cover?

The treaty has 29 chapters, dealing with everything from financial services to telecommunications to sanitary standards for food. Some parts have significant ramifications for members' own legal regimes, such as the part about "regulatory coherence," which encourages countries to set up a mechanism like the U.S. Office of Information and Regulatory Affairs to conduct cost-benefit analyses on new rules. The Office of the U.S. Trade Representative (USTR) has a rough outline. For a more comprehensive rundown, read this Congressional Research Service report.

7. How do negotiations work, exactly?

The negotiations have progressed in 20 days-long "rounds," which rotate between the party nations. Typically, the United States will table a proposal or circulate something called a "non-paper" for discussion, which gets marked up by all the participants until they can come to a consensus. In between the rounds, the U.S. trade representative will brief its 16 formal "advisory councils" and seek input from key lawmakers on where they have arrived. (Given the robust revolving door between USTR and industry, a certain amount of back-channel lobbying goes on, as well).

8. What's the role of Congress here?

In June, Congress approved "fast track" legislation that sets negotiating objectives for USTR to follow and requires an up-or-down vote within 90 days of the release of the text. If the agreement is rejected, the United States can try to renegotiate certain provisions, but such a large and unwieldy agreement might be difficult to open up again once it has been finalized.

Parts of this are an updated version of a 2013 explainer. More updates soon!