After spending two uber-intense weeks in Paris as part of the Rainforest Alliance delegation to the COP21 U.N. climate summit, it was amazing to see how governments, business and civil society came together to forge a historic climate agreement.  

It’s far from perfect. There are gaps: The emissions targets aren’t yet ambitious enough, and specific means for strengthening them and financing their implementation are challenges for a future day. But the agreement clearly signals a global pivot to a low-carbon world. Here are six takeaways from Paris that explain why:

1.  This time, it’s unanimous

In past United Nations Framework Convention on Climate Change (UNFCCC) agreements, only developed countries agreed to reduce their emissions. This time, all 196 countries — north and south, large and small emitters alike — have agreed. All countries have different but critical contributions to make. Emerging economies have agreed to a greater share of the responsibility. Nearly all developing and developed countries already have submitted plans for their "intended nationally determined contributions" (INDCs) to reducing emissions and addressing threats from climate change. About 75 of them include some form of forest protection, especially in tropical countries.

2.  Aiming higher (or lower)

Before the Paris climate talks, there was much debate about whether limiting warming to 2 degrees Celsius was even realistic. But the Paris Agreement went even further and aimed for a limit of 1.5 degrees. That’s a safer target for avoiding the most dangerous, disruptive and costly climate impacts.

3. Yes, it is legally binding

It’s widely accepted that this is an agreement with legal force, as the 2011 COP17 decision in Durban said it must be. It’s not any less binding than a "treaty"; technically it is a treaty. The Obama administration may downplay that, calling it an "executive agreement" because it doesn’t need to be ratified by the Senate. In fact, many international treaties with the force of law for the U.S. were signed by the president without going to the Senate. Unlike the previous climate treaty, the Kyoto Protocol, this one won’t be ignored by signatories on the grounds it isn’t ratified.

When governments, markets and businesses put a price on carbon pollution and account for it in their books; when land use is sustainable and forests and other ecosystems are restored and protected … that’s when we’ll know it worked.

All 196 countries are obligated to review their emissions reduction every five years, mandating a framework for ramping up goals over time. New ways of reporting and monitoring each country’s progress will provide transparency and help set up a race to the top. Each country still must determine and pass the domestic laws needed to enforce their climate commitments. But the Paris Agreement has given them more confidence and political will to do so.

4. Boardrooms on board

The private sector was more engaged in this process than ever before, with thousands of businesses, investors and trade coalitions involved over the past year. We have climate pledges from 5,000 diverse global companies representing virtually every industrial sector and over 90 countries. They include signatories to the American Business Act on Climate Pledge, the CDP/We Mean Business Coalition, the World Economic Form CEOs group, the B Team and many others. All together, companies pledging climate action represent combined annual revenue over $38 trillion — about half of global GDP — and the majority of the world’s market capitalization. Already, the global market for low-carbon goods and services is estimated at $5.5 trillion per year. The agreement should increase investor confidence and help the low-carbon share of the global economy grow.  

At the U.N. climate talks, Unilever and other big businesses announced plans to stabilize forest cover by 2030 and restore forest cover to 1990 levels by 2050. Hundreds of major companies are committed to eliminating deforestation from their supply chains, including those conducting about 90 percent of the global palm oil trade. Their support helped cement a prominent place for forest conservation in the Paris Agreement.

5. Forests’ role recognized

Forestry, agriculture and other land use account for nearly a quarter of global emissions, and are a key piece of the climate puzzle. Keeping forests standing has financial value for the carbon they sequester and the other ecosystem services they provide.

The Paris Agreement recognizes this, and devoted a whole section (Article 5) (PDF) to Reducing Emissions from Deforestation and Forest Degradation (REDD), sustainable forest management, forest conservation and reforestation. That signals the importance of forests to fighting climate change, and will help strengthen financial mechanisms that provide payments for effective forest conservation.

Hundreds of major companies are committed to eliminating deforestation from their supply chains, including those conducting about 90 percent of the global palm oil trade.

Meanwhile, negotiators largely punted on reducing emissions from farming and livestock. Even though they’re major emitters, the Paris Agreement doesn’t mention them except in relation to food security. But climate action plans should include revolutionizing food production systems for the billions living at or below the poverty level, so farmers can meet rising food demand and lower their emissions, increasing their yields and incomes on the land they’re working, without clearing more forests.

6.  Minding the emissions gap

For all its ambition, there are many other things the agreement does not address, and no guarantees about how we’ll tackle the hard part of actually fulfilling it.  

For example, there’s no legally binding obligation for wealthy countries to fulfill their pledges of $100 billion annually starting in 2020 to help developing countries combat and adapt to climate change. But there were some voluntary funding announcements, such as Germany, Norway and the U.K. pledging $5 billion over the next five years to reduce emissions from tropical deforestation.  

The agreement doesn’t put a price on carbon. It sets aspirational goals for emissions reduction that national governments will have to plan for and report on. But whether they do it through carbon taxes or fees or trading schemes or something else, and how fast they progress, remains to be seen — it will depend upon the steps of individual countries.

The difference between what the Paris Agreement and INDCs require countries to do, versus what they need to do to keep warming to 1.5 degrees, is called the "emissions gap." It remains wide, and it will take many agreements, and action on many levels — regional, national, subnational, municipal, markets, technology, civil society — to close it.  

But Paris clearly marks a turning point, the beginning of a transformation of the previous business-as-usual trajectory towards a sustainable global economy, which governments and businesses will pursue together. We’ll be able to recognize its success by the signs of progress we see in the years ahead. When the transition to decarbonized energy sources is accelerating; when governments, markets and businesses put a price on carbon pollution and account for it in their books; when land use is sustainable and forests and other ecosystems are restored and protected, then the emissions gap will be bridged and the agreement’s targets will be within reach. That’s when we’ll know it worked. With companies that control half of global GDP and counting already moving towards a low-carbon future, that day could be coming fast.