The Supreme Court is expected to rule this week on whether key provisions of the Patient Protection and Affordable Care Act are constitutional. This law ensures that all Americans can access the care they need at an affordable price.

Obamacare prevents health insurance companies from charging too much or denying coverage to those who pay for insurance but are suffering from painful and long-term “pre-existing conditions” such as heart disease or cancer. It allows people to pay into the health insurance system so that in case of emergency, they don’t have to tap into taxpayers’ wallets to pay for their recovery. And it levels the insurance playing field so that those who thought they couldn’t afford care now don’t have to choose between buying groceries and paying medical bills. Overturning Obamacare would leave insurance companies in charge of whether our fellow citizens can get the care they need or leave millions of Americans vulnerable to poverty or bankruptcy.

As the 32 million (and counting) Americans whose access to health insurance depends on the Supreme Court’s ruling on Obamacare hold their breath, here’s a quick look at the top three reasons why the health care law should remain intact.

1. Millions of Americans under Obamacare have access to affordable quality care who wouldn’t otherwise be covered.

The provision of the law that allows young adults to stay on their parents’ health care plans until age 26 has allowed an additional 3.1 million young people who wouldn’t otherwise have been covered gain access to insurance since 2010—in other words, 73 percent of American youth now are covered as a result of this provision.

The ban in Obamacare on pre-existing condition abuses by insurance companies will ensure that providers can’t charge more for or deny coverage to those who have painful, long-term medical conditions such as asthma, heart disease, and cancer. Approximately 60,000 Americans who were previously denied coverage now have insurance through the Pre-Existing Condition Insurance Plan.

The 350 community health centers created by the law have helped 50 million Americans who lived in medically underserved areas and couldn’t easily access insurance or health care.

Women no longer have to worry about arbitrarily being charged more for insurance or being told an essential yet sometimes expensive procedure or medication isn’t covered.

2. The Affordable Care Act lowers health insurance costs for everyone—especially those who need it most.

3. If Obamacare is overturned, all of us will be more vulnerable to unfair and unreasonable treatment by insurance companies.

In addition to banning insurance companies from denying or arbitrarily charging more for coverage to those with pre-existing conditions, the Affordable Care Act also eliminates lifetime coverage limits for 105 million Americans. This ensures that those who most need coverage to pay for expensive treatments and care cannot “max out” their health insurance or be denied vital coverage.

Rate-review provisions also protect consumers from unreasonable and inexplicable premium hikes by private insurance companies by increasing transparency requirements and accountability to rate increases. Insurance companies now have to publicly justify raising rates by 10 percent or more and the Department of Health and Human Services has granted millions of dollars to states to boost their abilities to stop these unreasonable increases.

Obamacare also has held insurers accountable for excessive profits, banning them from spending more than 20 percent of premium dollars on advertising or executive bonuses. About 13 million Americans will receive a rebate check from insurance companies that weren’t spending enough on patient care.

Obamacare bans insurance companies from charging women more than men—in the individual market, a total of $1 billion more—for the exact same plans solely because of gender.

Insurers are also required under the law to provide consumers with easy-to-understand information about their health plans and costs by September of this year, making it less difficult and daunting to figure out which plan works best for each individual or family—and much less probable that insurance companies can take advantage of those who don’t have access to this important information.

With this decision, the justices can rule either with Americans’ best interests at heart or in favor of corporate profits. The ball’s in their Court.

Emilie Openchowski is an Assistant Editor at the Center for American Progress.

*In this column, the term “gay” is used as an umbrella term for people who identify as lesbian, gay, or bisexual.