What Are the National Academies of Sciences, Engineering, and Medicine?

Key Takeaways

• The National Academies were chartered by Congress in 1863 under President Abraham Lincoln.
• They produce independent, peer-reviewed reports that inform U.S. science and health policy.
• Membership is a lifetime honor awarded through peer election in each discipline.

Chartered in Wartime, Trusted for Generations

On March 3, 1863, as the American Civil War entered its third year, President Abraham Lincoln signed legislation creating the National Academy of Sciences (NAS). The institution began with 50 charter members, selected from among the nation’s most accomplished researchers. The federal government had pressing practical needs, from improving navigation and metallurgy to standardizing weights and measures for military supply chains, and Congress responded by establishing an organization formally obligated to investigate, examine, experiment, and report on any subject of science or art whenever called upon by any department of the government.

That mandate, written into the original charter, remains legally binding today. More than 160 years later, the NAS still operates under essentially the same obligation, advising federal agencies, informing legislation, and producing assessments that reach into courtrooms, regulatory proceedings, and congressional hearings. What began as a 50-member body has grown into one of the most influential scientific institutions in the world, with reports that shape decisions ranging from nuclear waste storage policy to drinking water safety standards.

The definition of “science and art” for the purposes of federal advice expanded considerably over the following century. Engineering matured into a distinct discipline, and the National Academy of Engineering (NAE) was established in 1964 under the NAS charter. Medicine and public health warranted their own advisory body, and the Institute of Medicine was founded in 1970, also under the NAS charter. In 2015, the Institute of Medicine was renamed the National Academy of Medicine (NAM). The three institutions together form what is known as the National Academies of Sciences, Engineering, and Medicine (NASEM), operating under a unified organizational structure while each retaining its own membership and governance.

Three Academies, One Shared Operating Structure

The NAS, NAE, and NAM are legally distinct honorary membership organizations. Each elects its own members, maintains its own governing council, and pursues its own disciplinary priorities. The shared operational arm that coordinates their joint advisory work also carries the name National Academies of Sciences, Engineering, and Medicine, which can create some understandable confusion between the umbrella institution and the three constituent academies within it.

The table below summarizes each academy’s founding date and primary focus.

The combined membership of all three academies exceeds 6,300 scientists, engineers, and health professionals. The NAS draws from fields including physics, chemistry, economics, psychology, and biology. The NAE covers aerospace, civil, electrical, mechanical, and biomedical engineering. The NAM encompasses medicine, nursing, public health, and the biomedical sciences.

A great many NASEM reports require expertise from multiple academies simultaneously. A study on the health effects of air pollution might draw on atmospheric chemists from the NAS, exposure engineers from the NAE, and epidemiologists and clinicians from the NAM. The shared operating structure makes that kind of cross-disciplinary committee assembly straightforward. The NASEM is a private, nonprofit, nongovernmental institution. It does not regulate industries, administer federal grants, or enforce compliance with any standard. Its authority is entirely reputational, built through more than 160 years of rigorous process and voluntary transparency.

How Members Are Elected to the Academies

Election to any of the three academies is widely regarded as one of the highest professional honors in American science, engineering, and medicine. The process is peer-driven and deliberately closed to self-nomination. Current members nominate candidates from their fields, and those nominations work through a review process that weighs each nominee’s original contributions to research, professional standing, and breadth of impact on their discipline.

There is no application. Researchers can’t put their own names forward. Critics have argued that this self-selecting model may perpetuate existing demographic imbalances, and the academies themselves have acknowledged those concerns in various policies and procedures documents. Progress on gender and racial diversity among elected members has been uneven relative to the broader composition of the scientific workforce, though the academies have taken formal steps in recent election cycles to broaden the candidate pool.

Each academy elects new members annually. Election is for life. Approximately 500 current and deceased NAS membershave won Nobel Prizes, a figure that reflects the caliber of scientific achievement concentrated in that membership alone. Across all three academies, the total Nobel count grows considerably. New members who reach emeritus status remain affiliated with the institution but step back from active committee service, ensuring a degree of continuity across generations of researchers.

The Report-Making Process That Shapes Federal Policy

A consensus study is the primary advisory product of the NASEM. The process begins when a sponsor, typically a federal agency such as the National Institutes of Health (NIH), the National Science Foundation (NSF), or a congressional committee, asks the NASEM to evaluate a specific scientific or policy question. The NASEM assembles an ad hoc committee of volunteer experts chosen both for their qualifications and for the balance of perspectives they represent on the question at hand.

Committee members disclose potential conflicts of interest before appointment. Public information sessions, systematic literature reviews, private deliberations, and at least one round of independent peer review all precede publication of the final report. The process typically takes one to three years depending on the complexity of the question. Sponsors fund the work, but NASEM’s policies are designed to prevent sponsors from directing committee conclusions, a structural firewall that distinguishes consensus studies from research commissioned directly by agencies.

That firewall matters in practice because sponsors are sometimes the agencies whose programs the reports may scrutinize. A consensus study on safe drinking water levels funded by the Environmental Protection Agency (EPA) must be credible to environmental advocates and regulated industries alike. Independent peer review and the institution’s nongovernmental status are the structural mechanisms designed to sustain that credibility. Some researchers have raised concerns about undisclosed conflicts of interest in specific committees, including in the 2016 GMO crops report, which the NASEM disputed. That ongoing debate reflects the difficulty of achieving true independence when the scientific community is small relative to the scale of the questions it addresses.

A Publishing Model Built Around Open Access

The National Academies Press (NAP) is the publishing arm of the NASEM, and the way it distributes its output is worth understanding separately from how the reports are produced. The NAP publishes more than 200 titles per year and maintains an online catalog of more than 8,500 titles in PDF format, almost all of which are downloadable without charge.

The NAP started offering free content online in 1994, making it one of the first self-sustaining publishers in the world to provide web-based open access to scholarly material. In June 2011, the NAP removed remaining paywalls from its catalog, announcing that all PDF versions of its books would be downloadable to anyone free of charge. By early 2025, 25 million PDFs had been downloaded since that full open-access policy took effect. Print editions remain available for purchase, but the digital versions have been free for over a decade.

The practical consequence of that model is real. A public health administrator in a small municipality, a science teacher in a rural school, and a legislative researcher at a state capitol all have identical access to the same NASEM evidence base as a researcher at a major research university. Whether that accessibility consistently translates into better policy decisions is harder to assess than the download numbers suggest, and researchers who study science communication disagree about how often NASEM recommendations actually change outcomes on the ground. What the model does ensure is that the cost of accessing authoritative scientific analysis is not a barrier anywhere in the country.

Reports That Changed How America Thinks About Risk

On November 29, 1999, the Institute of Medicine released To Err Is Human: Building a Safer Health System. The report estimated that between 44,000 and 98,000 Americans died annually from preventable medical errors in hospitals. The figure generated immediate national media coverage, congressional hearings, and what many public health researchers describe as the founding document of the modern patient safety movement in the United States. It contributed directly to federal investment in patient safety infrastructure and accelerated the adoption of electronic health records across hospital systems.

The May 2016 Genetically Engineered Crops: Experiences and Prospects arrived after two decades of heated public and regulatory debate about genetically modified organisms (GMOs). The committee examined almost 900 research publications on the development, use, and effects of genetically engineered (GE) characteristics in corn, soybean, and cotton, heard from 80 diverse speakers at three public meetings, and received more than 700 comments from members of the public. The report found no substantiated evidence of a difference in risks to human health between currently available GE crops and conventionally bred crops. Within the month of its release, the report appeared in 144 news outlets and was downloaded more than 42,400 times from the NAP website.

The October 2020 Framework for Equitable Allocation of COVID-19 Vaccine was released before any COVID-19 vaccine had received emergency use authorization in the United States. The committee recommended a four-phase distribution framework that prioritized high-risk healthcare workers in the first phase, then individuals with multiple comorbidities, then essential workers in high-risk settings, then the general adult population. State health departments and local public health agencies across the country cited the framework as they built their vaccine rollout plans. The report was assembled far faster than a typical consensus study, an adaptation the NASEM made in response to the pace demands of the pandemic.

How the Academies Differ from Government Science Agencies

The distinction between the NASEM and a federal scientific agency is easy to blur. Agencies such as the NIH, the Centers for Disease Control and Prevention (CDC), and the EPA are part of the executive branch. They administer programs, fund research, regulate industries, and operate under political oversight from the White House and Congress. Their scientific conclusions, however rigorous, are produced within an institutional context that is subject to political pressure and can shift with changes in administration.

The NASEM’s independence doesn’t place it entirely outside that context. The questions it studies are chosen partly because federal agencies commission them, and sponsors inevitably influence the scope of what gets examined. A committee studying transportation safety funded by the Department of Transportation will naturally examine somewhat different aspects of the problem than one funded by a consumer safety organization. The NASEM manages this through independent peer review and conflict-of-interest policies, but the structural influence of sponsorship is real and is openly discussed in the institution’s own documentation.

The NASEM also differs structurally from professional scientific societies such as the American Medical Association(AMA) or the American Chemical Society (ACS). Professional societies exist partly to represent and advance the interests of their members. The NASEM, by contrast, is chartered to serve the public interest, and its reports are specifically designed to be credible to audiences outside any single professional community. That orientation produces a different kind of publication, one more likely to acknowledge uncertainty, weigh competing evidence, and resist conclusions that benefit one constituency over another.

The National Research Council (NRC), which serves as the collective operating arm of the three academies, is organized into seven major program divisions: behavioral and social sciences, earth and life studies, engineering and physical sciences, health and medicine, policy and global affairs, transportation research, and a Gulf research program. That organizational depth means the NASEM can address almost any scientific or policy question the federal government is likely to pose.

Science Advice During Rapid Change

The NASEM’s relationship with Washington is not static. The institutions that fund consensus studies shift priorities with each administration. Budget pressures can delay or narrow the questions that get asked. More structurally challenging is the tension between a deliberative model designed for thorough analysis and public crises that demand authoritative answers within weeks rather than years.

The COVID-19 pandemic made that tension visible in real time. The vaccine allocation framework produced in 2020 was assembled far faster than a typical consensus study, but even that compressed timeline meant the report arrived months after the original commission. The NASEM has since developed rapid expert consultation mechanisms intended to produce guidance in a shorter timeframe without abandoning the peer review standards that give consensus studies their credibility. Whether those faster mechanisms will carry the same institutional weight as full consensus reports is a question the research community is still working through.

The political environment also shapes how NASEM recommendations are received once they’re published. The institution does not govern its own implementation, and there is no legal requirement for any federal agency to follow its advice. The NASEM’s influence depends on a continuing social compact in which policymakers, journalists, and the public accept that independent scientific judgment deserves a protected place in the policymaking process.

Summary

Congress established the National Academies because a government at war in 1863 needed scientific advice it could trust not to be shaped by whoever happened to be in office. That original rationale has proven more durable than almost anyone involved in drafting the charter could have anticipated. The three academies that now make up the NASEM, working through the shared infrastructure of the National Academies Press and seven program divisions, have built an archive of consensus reports on questions ranging from the health effects of ionizing radiation to the equitable distribution of pandemic vaccines.

The institution is not infallible. Its processes are slow by design, its membership still reflects historical inequities in who gets recognized for scientific achievement, and its recommendations do not automatically become policy. What the NASEM does offer is something relatively rare in public life: a mechanism by which a large and diverse group of the country’s most accomplished scientists, engineers, and physicians can be assembled to examine a question together, subject their conclusions to independent scrutiny, and publish the results without charge. The artificial intelligence policy advice the NASEM is now being called to produce represents the latest iteration of exactly that function, adding one more chapter to a 160-year record that began with coinage standards and battleship hull materials in the middle of a civil war.

Appendix: Top 10 Questions Answered in This Article

What are the National Academies of Sciences, Engineering, and Medicine?

The National Academies of Sciences, Engineering, and Medicine is a private, nonprofit, nongovernmental institution chartered by the U.S. Congress to provide independent, objective scientific analysis and advice to the nation and to the federal government. It comprises three distinct honorary membership organizations: the National Academy of Sciences, the National Academy of Engineering, and the National Academy of Medicine. Together they produce consensus study reports, workshop summaries, and other advisory products used by federal agencies, Congress, and the general public.

When was the National Academy of Sciences founded?

The National Academy of Sciences was established on March 3, 1863, when President Abraham Lincoln signed its congressional charter during the Civil War. The charter obligated the NAS to investigate and report on scientific questions whenever called upon by any department of the federal government. The institution has operated continuously under that mandate for more than 160 years, making it one of the oldest scientific advisory institutions in the United States.

What is the difference between the three academies?

The National Academy of Sciences focuses on the natural and social sciences, the National Academy of Engineering covers engineering and applied technology, and the National Academy of Medicine addresses medicine, public health, and the biomedical sciences. All three operate under the shared operational structure of the National Academies of Sciences, Engineering, and Medicine, which coordinates cross-disciplinary report production. The combined membership of all three academies exceeds 6,300 scientists, engineers, and health professionals.

How does someone become a member of the National Academies?

Membership in any of the three academies is by peer election. Researchers cannot apply on their own behalf; they must be nominated by current members and evaluated through a review process that examines their original contributions to research and their professional standing. Election is a lifetime honor widely considered one of the highest recognitions available in American science, engineering, and medicine. New members are elected annually from nominations submitted by the existing membership.

What is a consensus study?

A consensus study is the primary advisory product of the NASEM, produced when a federal agency or congressional body asks the NASEM to evaluate a specific scientific or policy question. An ad hoc committee of volunteer experts is assembled, conducts public hearings and literature reviews, deliberates, and produces a report that undergoes independent peer review before publication. The process typically takes one to three years and results in a report that represents the committee’s evidence-based consensus on the question posed.

Are National Academies reports available to the public for free?

Yes. All reports are published through the National Academies Press and are freely downloadable as PDFs from the NAP website without charge. The NAP began offering free online content in 1994 and in June 2011 made all PDF versions of its more than 4,000 titles freely downloadable to anyone worldwide. By early 2025, 25 million PDFs had been downloaded since that full open-access policy took effect.

How many Nobel laureates are members of the National Academies?

Approximately 500 current and deceased members of the National Academy of Sciences alone have won Nobel Prizes. Across all three academies combined, the total Nobel count is considerably higher, reflecting the cumulative election of distinguished researchers in physics, chemistry, medicine, physiology, and economics over more than a century of annual membership elections.

Is the NASEM a government agency?

No. The NASEM is a private, nonprofit, nongovernmental institution. Although it was created by an act of Congress and frequently works at the request of federal agencies, it is not part of the executive branch and does not set regulations, administer government programs, or operate under direct political oversight. Its independence from government control is considered central to the credibility of its reports and is maintained through independent peer review and conflict-of-interest policies.

What was the To Err Is Human report?

To Err Is Human: Building a Safer Health System was a November 1999 report produced by the then-Institute of Medicine. It estimated that between 44,000 and 98,000 Americans died annually from preventable medical errors in hospitals, a figure that generated national media coverage and congressional hearings. The report is widely credited with catalyzing the modern patient safety movement in the United States, leading to federal investment in patient safety research and accelerating the adoption of electronic health records across hospital systems.

What role did the NASEM play during the COVID-19 pandemic?

In October 2020, the NASEM released the Framework for Equitable Allocation of COVID-19 Vaccine, recommending a four-phase distribution framework before any COVID-19 vaccine had received emergency use authorization. The framework prioritized high-risk healthcare workers in the first phase and established equity as a crosscutting consideration throughout all phases. State public health agencies and local health departments across the United States cited the report as they developed their own vaccine rollout strategies.