Think tanks (sometimes spelled think-tanks) are nonprofit organizations that conduct research aimed at providing policy advice and analysis to policymakers.

What is a think tank?

In general, there is great diversity in the think tank ecosystem and experts often note that there is no such thing as a prototypical think tank: these organizations differ from one another across several important dimensions, such as "in how they are funded, the roles that they play, their attitudes toward 'neutral expertise', their recruitment of staff, and their 'product lines.'"^[1] Moreover, the boundaries between think tanks and other entities with a mandate to supply policy advice, such as pressure groups, private foundations, academic institutes, policy schools, government agencies, and non-government organizations are sometimes blurry.

A stylized distinction may be drawn between "advocacy" and "research" think tanks, depending on whether the primary goal is to provide "ammunition" or "enlightenment",^[1] although these are probably best regarded as two limit cases in opposite ends of a continuum. Advocacy think tanks (sometimes called "ideological tanks" or "think and do tanks") often self-identify with a specific political ideology and offer their services to clients in a relatively well-defined range of the political spectrum. Examples include the Heritage Foundation and the American Enterprise Institute (conservative), the Center for American Progress and the Economic Policy Institute (liberal), and Cato Institute and the Reason Foundation (libertarian).

By contrast, research think tanks (sometimes called "ink tanks") are not antecedently committed—at least not explicitly—to policy proposals with a particular ideological bent and focus primarily on generating novel policy insights. A subset of these think tanks resemble academic institutions in many respects, and are as such sometimes referred to as "universities without students": organizations such as the Brookings Institution, the Russell Sage Foundation, and the Peterson Institute for International Economics, to name some examples, are staffed mainly by researchers holding doctoral degrees and publish their research in scholarly books or monographs, although these think tanks are usually  (but not always) organizationally independent of academia and have much closer contact with policy activists and a heavier emphasis on practical applicability. Other research think tanks, by contrast, operate in a manner more similar to consultancies: most work by the RAND Corporation, for instance, is focused on program evaluations requested and funded by government agencies.

The impact of think tanks on policy

Think tanks do not only differ significantly in their structure; there is also great diversity in the type and extent of their impact. Andrew Rich and Kent Weaver summarize:^[2]

First, [think tanks] can provide basic research on policy problems and policy solutions—for example, outlining the causes and consequences of skills deficits or slow economic growth. Second, think tanks can provide advice on immediate policy concerns through many points of entry into the US policy-making process. These include testifying before congressional committees, writing opinion pieces for newspapers and new media outlets, and writing policy briefs that are increasingly distributed in both print and Web-based formats. Informal consultations and dialogues are another vehicle for advice in immediate policy debates. Third, think tanks can act as evaluators of government programs, usually on a contractual basis. Fourth, think tank staff can be called upon to provide commentary on current events, both for the national and regional press and through new media outlets such as Web commentaries and blog posts. Finally, think tanks can supply personnel for government, given the relatively porous nature of the personnel system and in particular the substantial turnover of high-level, policy-making personnel that takes place at the beginning of presidential and gubernatorial terms.

Open Philanthropy has given grants to several think tanks working in a variety of areas, including the Center for Security and Emerging Technology (artificial intelligence), the Johns Hopkins Center for Health Security (biosecurity and pandemic preparedness), Dezernat Zukunft (macroeconomic policy), the Center for Global Development (immigration reform), the Good Food Institute (animal product alternatives), Nuclear Threat Initiative (biosecurity and global catastrophic biological risks), the Center on Budget and Policy Priorities (macroeconomic policy), and the Sightline Institute (land use reform).

In the United Kingdom, a think tank often cited as having had a major—though not necessarily positive—impact is the Institute of Economic Affairs (IEA), described by an author as "arguably [the] most influential think tank in British history"^[3] and frequently discussed as having played a significant role in the rise of "neoliberal" ideas in the 1970s and 1980s.^[4] Some have even claimed that IEA was causally implicated in key geopolitical developments beyond British borders: Sir Oliver Letwin, a conservative MP, once wrote: "without the IEA and its clones, no Thatcher and quite possibly no Reagan; without Reagan, no Star Wars; without Star Wars, no economic collapse of the Soviet Union."^[5]

A comprehensive report focused on American think tanks by a pseudonymous group of authors with familiarity and personal experience in the Washington D.C. think tank ecosystem summarizes: "Whereas the potential for impact is widely accepted, the average level of think tank impact is far more uncertain."^[6]

Think tanks and career choice

80,000 Hours rates working at a think tank highly in terms of impact potential, career capital and job satisfaction, and recommends this path for candidates early in their careers and suited for it.

The report cited in the previous section considers working at a think tank to be usually more valuable for its career capital—in particular, for growing one's professional network, improving one's understanding of the policy world, gaining policy-relevant skills, and becoming a recognized domain expert—than for its direct impact.^[6] The report also notes that the types of career capital think tanks help build vary considerably across different think tanks and roles within them.

Note that, generally, think tank work is considered to be a stage in a broader career in policy rather than a career in itself: "Almost nobody has a 'think tank career'—instead, see a think tank job as one possible part of a 'policy career'."^[6]